My Rival Coworker's Earnest, Excessive Love: Deep, Heavy Lust That Engulfs MeNewRival Douki no Hitamuki Kajouai: Fukabuka to Kuwaeru Omotai Yokujou; ライバル同期のひたむき過剰愛～深々と咥える重たい欲情～

Mikami Amane works in sales at an advertising agency, and she has never been good at love. One day she happens to witness her rival coworker Makino Ryōsuke crying over a broken heart. Though she tries to forget the sight, it lingers in her mind. Half a year later, Ryōsuke still wishes happiness for the woman who left him. When Amane murmurs that his ex-girlfriend is lucky to be cherished so deeply, he suddenly corners her with the words, "Then how about I treasure you?" What begins as teasing quickly turns into something far more intense. His cruel yet skillful touch and sweet, seductive voice overwhelm Amane, and she finds herself melting in ways she never expected. She cannot understand why her body responds so strongly to a man she only ever saw as a rival. As their stubborn pride clashes with undeniable attraction, the two coworkers are drawn into a heavy, earnest battle of love. Neither wants to lose, yet neither can resist the pull between them.