advice: how do you cum while WEARING the strap?

my fiancee (they/he) really likes wearing the strap during sex - i tend to bottom - and it works really well for us. ofc we switch and i get them off too, but we'd love to find a way for them to cum WHILE wearing the strap. i know there are double sided straps, but those are less preferred because my fiancee doesn't consistently feel comfortable with penetration.

i'd especially love to hear opinions from transmasc people who like wearing the strap. he's newly on T so i'm also wondering if there're some toys for those with bottom growth

thanks!