@DrHizzle Hm... I'd need a native (or a TL from a scan group or something), but I'm 99.99% sure that Line Japan works just like Line Eur, which is the same as WhatsApp: you right, they left.
First pic shows Ichi, so it should be him asking... Tho I admit it feels weird. Plus at the very bottom there's an almost obscured "Guess so" from the left that feels totally Ichi...
But that would make the "That's YOUR fault" Yamada's. Doesn't it feel off? Even when teasing straight to his face she's not usually this forward, or rather, this explicit?
Eh, whatever. The "progress" in this manga is random at best. We went from her giving him a ton of chocolate for V-day, to her yelling "Suki da" at the school gates, to her not being able to tell himb"I was waiting for you" or to ask for his Line. Maybe that line is yet another off-character Yamada.