Narita-kun, I've come to like you and what you bring to this manga a lot, but your presence is very much unwanted this time, so please leave and let the lovebirds alone at the dang festival :‑X
百合に挟まる男 (a guy that gets between the yuri)... literally.
I'm gonna forgive him only if he actually performs his duty as a wingman at the festival.
Well, it's not like he's doing intentionally. He very much just seems happy to be there with some friends. Plus he made it clear early on that he supports them.
Yeah, he's jazzed to do something his two friends are into, and like, it would be kinda mean to tell him to piss off after that.
That said he probably shouldn't have taken the middle seat.