Was fiddling with Unit 2-related stories..then ended up doodling, then colored over top of it. So many spoilers in my head and this may or may not be one. Lalalala
All things considered, I can't tell who the title's referring to. If I had to guess (instead of just saying both), I'd say Shion, but given Senma's expression (having somehow internalized wavy mouths as a person trying to hold emotion back)... alfjslkadjf... Clearly the solution is to write fanfiction in an attempt to goad you into pointing out personality fallacies.