つのらしちゃう
tsunorashichau

Godan Verb (su)
Godan Verb (u)

The completive aspect (contracted form) - indicates completion or regret of 募らす

1. to recruit/gather/collect (and it happens); to start to gather/collect (and it happens - often with a nuance of it happening unexpectedly or beyond control); to begin to feel (regret/sadness/etc.)

Completed Action
Colloquial