The twins little secret (OHSHC)

I pointed at hitaru and Hir-chan pointed at kaoru and I said " that's Hitaru." Hiromi said" that's Kaoru." They looked shocked and shook their heads. "No you got it wrong." They said. We looked at each other and turned back to them smirking" no we didn't." We turned and skipped back to the classroom waiting for our parents to come pick us up.

After 8 years Hiromi and Shigemi move back too japan but what is their reason for coming back and will the twins recognize them?

I don't own OHSHC