Sudden transformations are not at all a thing that phases Hajime much, this is just par for the course. There is still a quick double-take--there's no belt, no card--and he reflexively braces to be shot at, but no, she's attacking the Evilmon and there's...bubbles.

"Your bubbles are pretty!" Cutemon says helpfully.

"Hang on," Hajime tells him.

"Wh--YYYYY!!" Cutemon yelps and does as instructed, because Hajime has just jumped into the air and is now sailing at that Evilmon in a flying kick.

Sometimes, the old ways are best.