Nekottake!

High schooler Kensuke Fuji adores cats, but in a family full of people who are allergic, he's never been able to spend much time with the furry felines. When he meets the Ultimate Cat Whisperer, Kensuke finds a kindred spirit who seems to understand everything about cats! Deciding to become a disciple of this “kitty bonkers” cat-guru, Kensuke is on his way to learning the secrets of the Cat Fist Way, as a doorway into the secret world of cats opens up!

(Source: Dark Horse Comics)