I was so antsy I had to check the comments to make sure this didn't go the worst way possible.
Seems like that Iketani guy isn't malicious, just simpleminded. Legit thought Seiri was into him and that by confessing he could solve all her problems. Ignoring the fact that he was causing her even more problems.
Given how he backed off without any objection or hostility, it seems like he got the message. It's possible that in this case, he really is just a stupid highschool boy.