Rihito is the one who is fucking up everything. His sister is angry because he doesn’t even visit his own family even though he doesn’t live abroad and Japan is a small country. He skips all birthday parties, doesn't spend any time with them. He prioritizes Noa more than his family for bo reason.
It does feel like an axe, but it would be very weird to axe this after only like 8 chapters. Would be a first time this fast. Also this manga is fun and not bad at all.