In Part 1 Jun confessed his feelings to Erina, wanting to care for her, treat her right unlike her abusive and cheating husband; that only made Erina find temporary solace in Jun to finally have sex with him, but she didn't want to trouble a high-school student as an older 35 years old lady, so what she had with Jun only gave her courage to divorce her husband, moving away from the apartment thus Jun never saw her again, regretting not being able to keep Erina in his arms,
Part 1 ended with the sequel hook where Jun met Erina again 10 years later, and here it is, on Part 2 Jun admires Erina even more as a 45 year old lady, now working in a restaurant she owns for about 3 years, finally free and independent, he immediately asks Erina if she married again, no she says, she is too old for that, but her clients do notice how beautiful it is, Jun tries his luck again but Erina shoots his down politely, however, he doesn't give up, actually waiting Erina after worm hours.
He goes to her home, they reminisced about the past, their short fling, Erina insists she is not pretty as a 45 year old, Jun disagrees, insisting she looks beautiful as always, even better actually; they give in into their desires, Jun insists he wants to seriously be with Erina, now he in an adult, he can take care of her, Erina sheds the reminder of her reluctance. In the end Jun married Erina, quit his job to co-manage Erina's restaurant and take some part-time jobs on the side to fully support Erina, Jun is happy he has a home with lights on, with someone there to greet him; Erina happily greets her husband back while breastfeeding their child, Jun is a little embarrassed for Erina to show up at the door with her boob out, happily asking her husband what he would like to eat, herself perhaps; THE END.