Secret Class - 300

21st Century, Accident/s, Adopted Protagonist, Adoptive Mother Turned Lover, Adult Male Lead, Adultery, Affair/s, Ahegao, Armpit Licking, Beach Intercourse, Beautiful Female Character/s, Beauty Mark, Big Ass, Big Breasts, Big Penis, Blonde-Haired Female Lead, Borderline H, Caught in the Act, Cheating Wife, Cheating/Infidelity, Death of Loved One/s, Doggy Style, Familial Love, Fellatio/Blowjob, First-Time Intercourse, Full Color, Handjob, Harem Subtext, Innocent Male Lead, Inseki, Intercrural Intercourse, Kiss/es, Lust, Male Protagonist, Masturbation, Milf/s, Naive Protagonist, Netorare, Netori, Nipple Play, Older Female Younger Male, Plain-Looking Male Lead, Plain-Looking Protagonist, Red-Haired Female Lead, Rivalry, Sex Training, Spanking, Sumata, Threesome, Virgin/s, Webtoon, Webtoon/Webcomic