Ahh... that actually makes sense. I think I'm vaguely remembering that promise from the anime episode these last three chapters were used as source material for. And man, is that going to be quite the shock for them whenever they do find out that they both like Raku and have been passively helping the other get closer to him, whenever that might happen.
Still, it's really adorable seeing them collaborate on a project like this, not knowing they're both doing it for the same guy.
And, hey, salty chocolate is totally a thing, isn't it? Chitoge didn't do all that bad, honestly. She still gave him handmade chocolates.
Cute moment with Kosaki, too, yeah. And then there's his guys at home giving him way too much on top of all he had today... ugh...