Aishiteruze Baby ★★, Vol. 2

Kippei is busy trying to become Kokoro's boyfriend and slips back into his irresponsible ways. He oversleeps and doesn't have time to make Yuzuyu's lunch. Even worse, he spends an afternoon with Kokoro, forgetting to pick up Yuzuyu at kindergarten. Yuzuyu feels like she has become a burden to Kippei, so she decides to walk home by herself...and ends up disappearing! -- VIZ Media