I'm a vindictive bastard. Not all the time of course. You don't get to run a chain of convenience stores without a degree of likeability. In fact if you met me, that is the first thing you would note. I am extremely affable. Just don't cross me. I will extract vengeance on you. Not revenge; vengeance.

OK you want examples. I used to play rugby, still do occasionally. I was a lock, one of the second row forwards; tall, well set, fairly quick on my feet. So I was chasing down a high ball and this lumbering fuck No. 1 of a loosehead prop hits me while I'm jumping for the ball, and I land hard, wrecking my shoulder and getting a slight concussion. The ref ruled it accidental. The trainer subbed me while they sorted the shoulder and the team doctor gave me the all clear.

I got back on the pitch and the big fuck grinned at me. Stupid cunt just confirmed that it was a deliberate foul, so next scrum I marked his card for him. He wasn't sure it was my fist got him and the ref didn't see it, but that was only for starters.

As it turned out, fortune favoured the brave. Their No1 got the ball and went on a blundering run. He was brought down and the ruck was set but he set the ball back nicely for their scrum half. He was taking his time marshalling his backs and I saw a chance. I heaved up from below my opposite number in the ruck, catching him of balance and sending him into the No 8 and falling onto the loosehead's arm.

Unfortunately for him he had his hand on the top of the ball and the weight of the two boys broke his forearm. I came up with stud marks on my face and neck where a boot had caught me, and nursing my shoulder again. None of the officials saw anything untoward, and as their No 1 was helped off he looked hard at me. Since at the time I was getting treatment he couldn't figure if I had any hand in his injury. But I knew, and that was enough. I'm not stupid enough to get into a vendetta.

Now, OK, I got lucky that time. The opportunity arose and the outcome was better than I expected. I had thought they would land on him and just slow him down, so I could take him out hard, later in the game, but you get the idea. Fuck with me, and I will fuck right back.

Looking after the accounts for the stores gives me a fairly good overview of what sells when, and what sort of money should be going through the accounts. I am also pretty quick to spot irregularities on a till. Most of my staff are wives, single mothers and students. Not the sort of people who have a lot of disposable income. So to remove temptation as much as possible, they get a massive staff discount. They can also have any date expired food, on the understanding it is for their use only. Basically I try to make it not worth their while stealing from the stores. The wage is better than average, because the stores are profitable, but the perks make their money go further.

So, when I saw my wife was withdrawing a lot of cash from the joint account, I sat up and took notice. I make a good living from the stores so I don't have a problem with my wife spending money. I don't believe in credit cards, so she uses the debit card, rarely cash.

Two other things you should know about me. Despite how the incident on the rugby pitch might seem, I plan things through. On the pitch you get the ball and read the game. Seconds make the difference between making a score or not. Real life is different. That is why I bought the stores that would make money, not the ones on the other side of the road, or a few hundred yards away. The other thing is that I loved my wife with all my heart. I needed to know what she was doing with the money before jumping to the conclusion that the bitch was playing away.

OK, I know I was already there but that is part of the vindictive aspect of my character. I assume the worst. Luckily, my rational side is strong too. Hell she might only have a gambling addiction, or maybe she's just using some weed. For all I know she might be saving to buy me a nice present. Or to get ready to run.

How the hell was I going to play this? All my stores have cctv and security systems, linked into a computer system. Some of the cameras over the tills are almost invisible if you don't know they are there. But did I want my house bugged? I thought it best wait till she's out of the house and check stuff myself. Get something to work on.

The stores pretty much looked after themselves, and I had the office work well looked after too, so, I took a little time to myself to think about my next move. I was wandering along the High Street and went into the phone shop. I'm a sucker for gadgets. They were promoting some software to download all your phone numbers from your sim to your computer, so you won't lose them. It gave me an idea for a start point. I would download everything from our phones to the computer and then I could search her numbers.

That evening I loaded the software.

"Sharon! Give me your phone."

"What for?"

"I have this new software that save all your numbers so if the phone fails, you can re-load them from the computer to a new phone. Saves you having to get everyones' number and punch them in."

Hesitation.

"I think my battery is flat"

"No problem. It links through the USB so it will power from the computer. Just shows how useful a tool this could be. If it had been a faulty battery or something it might have corrupted the data."

Reluctantly she handed over her phone. I created a folder for her data and downloaded it straight to the machine.

"OK. It's in a folder in "My Documents" called "Phone Numbers", under your name, if you need it."

"Is there a password?"

"No, just go straight to it, if you need it." I went onto the internet and started browsing for classic cars. I fancied an E-type if I could find one.

Eventually Sharon had soaps overload and went to make a cup of tea. I quickly copied her file and e-mailed it to myself at work.

Normally I didn't bother checking Sharon's phone bill, it was paid by direct debit. Things were different though. I lifted the folder from the desk drawer and took it with me to work. Firstly I checked through her phone numbers. Strangely, I recognised my problem the moment I saw the name Steve Reilly. A quick check on the phone records showed me she was phoning him a couple of times a day.

Steve Reilly not only was a competitor, but he was also a football player. To me as a rugby player, that was probably worse. Now I needed confirmation that they were in fact having an affair and using my money to pay for it. I couldn't see any other option than to get a private investigator onto the job. I would have no problem taking time off work, but I'm a big fucker and I would stick out like a sore thumb trying to follow either of them. I checked Yellow Pages and got a company in a town ten miles away. I could have got the company that did my security work to do it, but they were the best in town and I figured Reilly would use them for his shops too. I didn't want to employ someone with a conflict of interests

I set up an appointment, and took along a couple of photos of Sharon. The PI was an ex-cop who seemed pretty prosperous, judging by his premises. Either that, or a flash git, bluffing his way. Anyway all I needed was proof of the nasty so he didn't need to be Sherlock Holmes. He told me a week should cover what I wanted and I stumped up a thousand quid as a retainer. As I drove off I noticed I needed petrol, and pulled into a small petrol station.

As I filled up the motor I looked around and my gut told me I was looking at an undeveloped goldmine. I went in to pay and realised it was a husband and wife business. They were in their sixties, and I got talking to them. Long story short, they wanted to retire but hadn't got around to doing anything about it. I asked them their price, knew it was about £250k under its potential, and told them to get a valuation. I gave them my card. Look, I may be a businessman but I have to look at myself in the mirror every morning. I might take vengeance but I don't take advantage of people, and I don't cheat ... much.

A week later I got two phone calls. One rather apologetic, from Mr and Mrs Flanagan, saying they had been told the business was worth pretty much what I thought. They were astounded when I agreed the price and asked for their solicitors details. The second was of course my PI telling me Sharon was playing away, but not just with Steve Reilly. She had met a different man for lunch and then Steve in the evening, when I was at training. I told the PI to get me further details.

I drove down to give the PI another thousand and to have a look over my new acquisition. The PI had photos of Sharon with Steve, and with the other guy, in public, but hadn't got anything sexual. I gave him the second instalment and told him to get something that would stand up in court, proving infidelity, and an identity for the second man.

I sat pat for another week, fulfilling a husband's bedroom duties. Hey, a fuck's a fuck, and you get it when you can! Sharon didn't seem unusually reticent, nor unusually eager. Nevertheless oral was out. Not that that was unusual during the week. I wasn't worried about STDs since we used condoms. Sharon wouldn't take the Pill as it made her gain weight.

The following Friday I got what I needed. Paramour number two was a guy called Jim Leonard, a sales rep for a company that sold those bagged sundries you see corner shops and stores like mine. You know the sort of thing. Sewing kits, those small rolls of insulation tape, electrical fuses. That sort of stuff. They used his flat twice that week. Steve Reilly and her got a little beauty spot car park action while I was at training. I had enough to know my marriage was over. I figured she would be on the rag shortly so her activity would dry for a week. I put the first part of the plan into action. I got some chillis from the store and extracted chilli juice. I smeared the crotch of a few pairs of her knickers. The "big" ones at the bottom of the drawer that she was likely to be using soon. I also got a hypodermic and injected some of her tampons. I'd heard of some guys using wintergreen for a practical joke, but I reckoned she might smell it. I hadn't a clue if it would work but it seemed reasonable.