I like ABO as a.. trope and I do believe their can be consent, admittedly fair and between.
https://www.mangago.me/read-manga/shinnyuu_shain_no_omega_desu_ga_senpai_alpha_kaizoushimasu/ this is an ABO with consent, though MC did get assualted by a stranger that the ML attacked. Along with ML getting possessive in one screen but he got better. Of ......
