I had a player like this once. He wanted to play an edgy, angsty rogue, whom(you guessed it!) wore a fucking outfit like Assassins Creed. Of course, being the generous DM I am, I allowed him to make his character as long as it was ahead of time so I could write him in without trouble. The group was 5 players. A spellsword, fighter, cleric, stone-hurler(lol), and the rogue.
I also I knew these people and was good friends with 4 of them except yours truly. He was friends with the guy playing the cleric. The rogue only made it through 3 sessions before I decided I was sick of his shit and we unanimously chose to screw him over. The good part was that he didn't care that we killed his character. He still came to our sessions and played Runescape the whole time.
Here are some of the things he did in the sessions he played:
-We started off in an Adventurer's College. He wanted to build a sniper rifle. He wasn't proficient in either firearms or tinkering. I offered him a 1d10 Musket and a low build cost, but he insisted in be "modern." He argued for almost 30mins. He still took the damn musket. I even let him change his Feats in order to be proficient in firearms.
-Got locked in a ranged battle vs some Pirates. Our spellsword and fighter were pinned and out of ranged options. Mr. Rogue chose to use 1d6 throwing knives instead of the fucking Musket despite my straightforward suggestions.
-He got mad and attacked a woman at the pub because she didn't care for his rather blunt and crude sexual advances. He had 9 Charisma. I later find out he put his highest ability score in intelligence because he wanted to be smarter than the rest of the group.
-He would always try to split off from the group. I thought it was interesting and rogue-like, but he would end up knocked out and the group had to save him.
-Fought our spellsword tooth and nail for a Dai Katana which I wrote specifically for the spellsword to use. It was a reward from an earlier quest.
-he also tried to fudge rolls which once I figured it out, I made the campaign a living hell for just him
-he died after jumping onto a Dire Crocadile and failing the Strength save to prevent a Death Roll