I think that for me, fun varied with the mood I was in.
When I was younger, I used to read what I considered at the time, a silly series called The Destroyer with a character called Remo Williams. Now, Remo was kind of dull, but his mentor and trainer Chiun was truly the stuff legends are made of.
Not legends like Alexander the Great, comedic legends. The writers really had fun with this guy. Being older, I find the books to have staled with age, as the original pair of authors is no more. Richard Sapir and Warren Murphy somehow co-wrote these books working on them seperately. But, for me, when Sapir left the series before his death, that's when things got stale for me. Anyways, I would buy the books and skip through to Chiun's dialogue, just for the silly comments.
So, I made a super-reflexes scrapper called Klang the Trite. For some inexplicable reason, I wanted to make Klang similar to Chiun. I made him have a crush on Connie Chung, despite her marriage to that "Pale Piece of a Pig's Ear", Maury Povich. He also found Soap Opera's to be "lovely dramas".
The unsettling thing was that teaming with him was difficult, as he would want to be paid for his efforts. And his manners were a bit atrocious.
The dialog I used for him, well, I had a fun time with it, although I'm sure others were scratching their heads when I'd get an invite, I'd accept. But, I told them I couldn't possible risk my life for less than 1000 influence, payable in gold. And, the more difficult the task, the more I would ask for. Some gave it, as it was a nominal fee, others would just figuratively go "huh?". Some just kicked poor Klang without further comments.
Because he was an RP character, I put him on Virtue. But, because I'm a Liberty player at heart, Klang didn't get much love. His earnings are still embarassingly low for a highly esteemed Korean assassin. However, I believe he is still in @Sgt Pandora's sg on Virtue, or was at the game's end. I felt badly for not playing on the server much, but I think for some of us, we get that feeling of guilt when we're not on our home server. Eh, maybe that's just me. <shrug>
Aside from this character, I kind of have a tie for 2nd. Ukase Rex my main, ice/ice/Mace blaster (my badge toon, I want to say 1339 at the game's closing.) and Molten Heat, Fire/Mental/ Cold, another blaster (one of my two different characters to get The Really Hard Way. Loved that trial - mainly the epic fight against Cole in the end, avoiding the lightning.)