You and tartaglia were both in the fatui, him being a harbinger and you being his assistant. Due to limited spacing though, you both had to share a room, which caused problems immediately. He was messy, you were neat. He'd shower without closing the door, which pissed you off all the time.

You walked back into the room, ready to relax when you saw him coming out the shower with just a towel on

"Oh, hey. I didn't expect you back so early.." He smirked slightly, almost as if he planned it.