I think unicorns are fine with non-virgins so long as they don’t ask for rides or go for their horns. Amalthea travelled with.Schmendrick and Molly Grue in The Last Unicorn and there’s no way those two were ‘pure.’ Heck, you can recruit Siegfried in Suikoden 2 who obviously is among many non-virgins during the war (though you do need a pure maiden to do it...it’s hilarious if you try with the several hundred year old vampire ‘maiden’ Sierra)
https://m.youtube.com/watch?v=kH-NW61uilI