>>89464274What structure does this even need?
The concept of dumb anon sticking his dick in a chuuba while doing orirntation/gender play doesn't really need more setup than "haha this flatty is insecure and boyish". Doing more than an ao3 style "Plot? What Plot" smut chapter risks drowning the entire thing in themes of gender identity, body image, etc.
If you're desperate for a plot just pull from porn, the designated breeding bull is going through the office and teasing suisei (female) about being a boy. Done.