Once he starts chasing after him, it's not with reckless speed, instead his eyes are keeping track of Kokichi's every move. In reality he's not chasing after his wallet,but something much important to him—Kokichi's motivations.
Getting his wallet back would be nice too, though.

He stood there with a dumbfounded look on his face for a few more seconds until he was able to snap out of his thoughts, his eyes widening slightly as he returned to the present moment.

"Kokichi-"

His name leaves Shuichi's mouth with a sharper edge than he intended.

He knows there’s more to Kokichi than the chaos he leaves in his wake—so much more.
Shuichi can’t help but feel a magnetic pull towards him—not towards the mask, but what’s hidden beneath it.
He wants to understand this lonely boy, now running away from him after playing some childish prank.

Was he really becoming too soft? The phrase digs under his skin,the realization hitting him like a wave washing over him.
It was true—he was too quick to embrace and accept the stillness and warmth on his back,wasn't he?
He isn't as wary of him as he used to be,that's for sure.

((yes i am i love you