Araki-kun wa Kainarasenai

Yakko has always lived in the shadow of her model/actress younger sister, Yuno. So when she's surprised on her 17th birthday by super-popular actor Araki Shigaraki, she assumes he's looking for Yuno...until he declares his love for Yakko?! Not only that, he'd declared his love for her before...but now, as then, she doesn't believe him! But he's determined, and if she won't see him as a boyfriend, maybe she'll see him as a pet...?!

(Source: Kodansha USA)