Sameee! Used to watch those yaoi amvs on youtube, and at that time junjou romantica, loveless, Sekai-ichi Hatsukoi and sex pistol were the peak yaoi anime and the starter pack
What a coincidence! The same happened to me too. Koisuru Boukun OVA on YouTube is the first I watched that got me interested in the Yaoi world.
Then, leads to more yaoi anime like Kuro-stalker-san mention junjou romantica, loveless, Sekai-ichi Hatsukoi, Sex Pistol. As for me, Ikoku Irokoi Romantan, Maiden Rosa, Okane Ga Nai, Kirepapa, Level C, Love Stage, Papa to Kiss in the Dark, Sensitive Pornograph, and my personal favorite,” You’re My Love Prize in Viewfinder.”
Re reading this again, koisuru boukun is one of my gate in entering yaoi world in my childhood, that I develop a fetish for a tsundere bottom until this day