Ou-sama wa Hana ni ka Shizuku

"I've had a crush on you for 10 years. Today, this time, I won't miss this chance —” Hiiragi has just broken up with her boyfriend. Then, at just the right moment, Rikumi, a junior acquaintance from her college days, who is now a handsome, perfect gentleman who is nicknamed “The King” by everyone around him, shows up at her door. He tells senpai that he knows everything that's been going on with her, and confesses to Hiiragi that he has been in love with her for more than a decade…! He pampers Hiiragi both physically and emotionally… A story of doting, obsessive love! (Source: Shogakukan, translated)