[On the contrary, at the mention of 'friends', Seto's eyes light up.]

Then it's decided! You and me are friends starting right now. [He's not so easy to get rid of, anyway.] Besides, just 'cause we're in different grades doesn't mean we won't see each other. We can eat lunch together or something. [Is that allowed? Heck if he knows.]

[He turns towards the school gates, but doesn't walk away quite yet.] Where d'you live? Might as well walk together.