Reichu: Apparently, Sachi's gills work both in and out of the water — very interesting. Considering that he's powered by a Super-Solenoid, I find it odd that he needs to actively respirate in order to regenerate — but, then, even harpies need to yawn. It's unfortunate that this shot doesn't include the top of Sachiel's pelvis; if his nostrils were included in the shot, we would've been able to see his entire respiratory process.
Kendrix: This looks like it's supposed to be some sort of cooling process.
Keisuke-kun: See, even poor abused Sachiel is sweating in the sweltering heat that is Japan.
Reichu: It does almost look like there are little sweat droplets on his gill lids… Though, as the operator-babble from 097 confirms, Sachiel's flesh has actually melted (or “fused”). Ouch.