Don't Let Anyone But Me Make Your Heart Race

Thanks to his tenacity, college student Rio has just landed himself his first boyfriend: the suave and mature club bartender, Chiaki. But while Rio obsesses over his mega hot "Mr. Perfect," he also begins to worry he might not be good enough for him. Then, when Chiaki gets the idea that Rio wants to break up, he suddenly grows desperate. Turns out Rio's new boyfriend is actually quite (endearingly) clingy!

(Source: MangaPlaza)

Notes:
- Originally published as a two-part story and later picked up for serialization under the title "Hatsu Kare Double-Sided (初彼ダブルサイデッド)".
- Includes the one-shot "Renai Antithese (恋愛アンチテーゼ)" and one extra chapter.