Not bothered at all; to not care in the slightest (emphatic).
その噂は少しも気にならないよ。
I don't care about that rumor at all.
彼の批判は少しも気にならないと言っていた。
He said he wasn't bothered by the criticism at all.
値段が高くても、品質が良ければ少しも気にならない。
Even if the price is high, I don't mind at all if the quality is good.
部屋が散らかっていても、彼女は少しも気にならないらしい。
Even if the room is messy, she apparently doesn't care at all.