Wow I've just replied extensively to a similar post below. It's not 'started' per say, but I'd say I was 'introduced' to yaoi when I was 10.
More than the sexy content, I think the whole bunch of misconceptions and weird fucked up generalisations in yaoi are what makes it a no-no for 'unaware' underaged people. Idk how I survived, really. I think I grow up decently (l o l).
that time, I just clicked some cute kiss scene on YT, but actually find video about misaki x usagi-san -without conscious, it's make my heart stopped. how cute~~ with thingking like that,
and accidentally going crazy with a lot of yaoi drama cd while read it's manga, from then on I can't stop myself reading yaoi / shounen ai manga.
I started reading slash at 17 then yaoi at 19, so I guess I'm an old maid haha
I knew about yaoi but I wasn't interested and nowdays I see what I've been missing ( http://www.mangago.zone/read-manga/razoku_no_hanayome/ )
i was like 8 when i saw junjou and i started around the same time
Honestly how old were u guys when u started reading ur first yaoi, I was like 12 or 13. I wanna know if I'm the only weirdo that started like that