He isn't dense, he made a move on her and she rejected him. Even in this chapter she's thinking about rejecting him when he notices the heart. Male characters always get blamed when the girl continuously shoots herself in the foot, it sucks.
This series is nice and all but I don't want rabbit to end up with fox. Selfish pushy girl continuing to be selfish and pushy and getting what she wants is annoying.
Better not be setting up an Aki x Shiho ship. Never really been a fan of side ships, especially when the loser of a love triangle is immediately put together with someone else. Plus Shiho is just straight garbage.
It's like the MC wasn't trained by a special ops soldier for years. He's just so typical, he doesn't have any suspicions towards the twins at all. Or even fear they could be used against him.