ふっと
futto

Adverb

1. with a whiff; with a puff

Onomatopoeia
そして、どうすることも出来 できない物憂 ものうさに、ふっとため いきをつく。
soshite dō suru kotomo dekinai monōsani futto tameikio tsuku.
And then I breathe a sigh from melancholy in being unable to do anything about it.
Adverb

2. suddenly; abruptly; without warning

その かね ると かれはふっと ぬすみたくなった。
sono kin'o miruto karewa futto nusumitaku natta.
The sight of the money tempted him into stealing.
Other forms: