It's definitely Sebastian. Here is my confession that I've been meaning to get out for several weeks: I was in love with him the second I saw him, way before I'd even heard of Kuroshitsuji.
"I'm Garrus Vakarian and this is now my favorite spot on the Citadel." adult - she/her
Well.... a tattoo... That's stretching. But I like where your fangirlishness is going. Confession #2 of the day: I have Sebastian posters all over my room. Literally. And my parents are never in there, so they still have no idea who the mysterious Sebastian I'm always going on about is and don't seem to care. They never ask, anyway.
"I'm Garrus Vakarian and this is now my favorite spot on the Citadel." adult - she/her