Tough call, I've used so many...
I think it's probably one of my RWBY characters, Chunlan Zhu. She's a girl with a lemur tail, whose Semblance (a power unique to each person) made it so she didn't need to sleep. She was just slightly off-kilter. Not really crazy, but her extended span of full consciousness has caused her to act in strange ways at times. She often daydreams and gets distracted in the middle of a fight on a regular basis and comes off as stalker-ish because she has developed a habit of memorizing other people's schedules (to figure out when they go to sleep and wake up, she she can leave them alone at night and start bothering them first thing in the morning.)
She fights using a modified monk's spade which houses a motorized spool of high tensile-strength mono-filament wire, and her constant state of conciousness has allowed her to learn so neat tricks she can use that wire for in combat situations. Everything from creating tripwires to garroting enemies or entangling them.