Personal opinion, no mod hat here:
Clothed hugs and kissing with closed lips on hands, cheeks, nose, boo-boos (minor wounds) and top of head is
generally considered G-rated, no matter the parties. Kissing the lips or with an open mouth on 'public' areas between any two beings counts as shippy, even though still fairly teen-rated.
Looking at fics and the asks on fanwork exchanges on AO3 has taught me much about the wide array of Mature and Explicit content out there.