Is the transfer student their future son? So Umi dies like 15 to 20 years in the future? But he doesn’t seem to care much about the MC? Is the MC secretly losing his lifespan and giving it to Umi when her heart races? But then wouldn’t the transfer student be stopping that? Wait I’m overthinking this. The transfer student just threw a huge mystery in what I originally thought would be a lighthearted simple romcom; now I am the confused.