Tohru is a dragon who can live for a VEERY long time
Kobayashi is a Human that is limited by age...it will not end happily unless a spell comes involve.
You gotta love how Fujimoto built up the tension and suspension leading up to that moment. The panel work is always good with him
Maybe a little too well for Spear Hero tho...dear gosh
Then he utter GROW UP! Your buddy yells at ya, sleep it over, shrug it off and laugh it off with them (maybe after a talk of course).
All for one