Wiktionary
zipless
a. 1 Without a zip fastener. 2 (context informal figuratively English) Without complications and hindrances.
Wikipedia
Zipless
Zipless is the first solo album by singer Vanessa Daou, released in 1994.
Usage examples of "zipless".
The school board would really be on her backside for recommending books about zipless fucks to fifteen-year-olds.
Next thing you know we could be into what Erica Jong calls the Zipless Fuck.