Keito is deaf. He becane friends with Aoi, an actor that can amazingly express his words through movements. Aoi has been patient with Keito, carefull explaining the words he might not understand. For that Keito kisses Aoi as a confession when he asked what Aoi thinks about a deaf dating a hearing one when Aoi answered "You would do fine". I stopped at 5.2 where Keito thinks he's the reason why Aoi quit being an actor.
Chameleon wa Tenohira ni Koi wo Suru