No that's fair, he'd want to make sure that particular line is a clear one if it's going to be crossed. Even if Shinji is, yet again, still not actually well versed in how these things are supposed to go. Like, at all.

"Y-yeah, I mean... if you're okay calling it that." He's pretty sure his heart's going to explode from all of this, but at least the position he's put himself in means the only way that bit of information is getting betrayed is the blush hitting his ears and his words becoming that much more shy, "Then, right. Boyfriends."