With the looming threat yet unknown, there's only undeniable pleasantness to soak up with this drawn out kiss. As Kai parts, Shinji leans forward just a touch, as if to chase that smooch down for a tiny bit longer.

The explanation is a nice enough alternative, one that Shinji replies to with a soft, surprised, "Oh...!" That! Sure does explain the sudden outpouring of affection, not that he necessarily needed it, but also keeps any worries of needing to see people for any sadder reasons at bay. This is all good, all very good, even if the thought of Kai actually reading what he'd written sends his heart fluttering.

"That... was fast," is what comes tumbling out of his mouth next, accompanied by some of that familiar color rising to his cheeks.