girls help x

i’m nearly 15, me and this boy (16) were messaging in june and things were getting serious however we never properly met outside of school . we started talking again and i want to go to his , problem is i’ve never done anything with a boy and in previous relationships he’s gone all the way. i can’t speak to my mum about this so this page is my help.. what should i do

side note ; obviously i’d never have sex until the legal age and the furthest i’d go is just third base