The story
From diaper (“an absorbent garment”) + -gasm (a suffix that denotes a method of orgasm).
Etymology from Wiktionary, CC BY-SA 4.0.
diapergasm
dia·per·ga·smToday it means: An orgasm or orgasmic-like sensation caused by sexual stimulation with a diaper; an orgasm achieved during diapersex, or while thinking of diapers (diaperstuff). Full definition →