All Grown Up.When the seventh-heaven ecstasy from their first kiss dies down, Mikako and Tsutomu quickly find that the epiphany of their new-found romance is the preamble for a whole different anthology of problems as evidenced by Mariko finding in Ayumi a new rival for Yuusuke's heart. Mikako and Tsutomu decide to take the train back home oblivious to Mariko silently fuming at Ayumi as she awaits Yuusuke's arrival; a wardrobe interchange later, a perplexed Ayumi watches Yuusuke speed off with Mariko in tow as she tries to wrap her mind around the past Mariko has with both Yuusuke and Tsutomu...