Eleceed

Jiwoo is a kind-hearted young man who harnesses the lightning quick reflexes of a cat to secretly make the world a better place—one saved little child or foster pet at a time. Kayden is a secret agent on the run, who finds himself stuck in the body of a...um...decidedly fat old fluffy cat. Together, armed with Jiwoo's super powers and Kayden's uber-smarts, they're out to fight those forces who would let evil rule this world. That is, if they can stand each other long enough to get the job done.

(Source: Webtoon Entertainment)