AGE GAP IN A LESBIAN RELATIONSHIP. WEIRD OR NAH?

I'm currently writing a book between two characters that meet at 18 and 27 respectively, and begin a romantic relationship at 20 and 29. The story only makes sense if they're individually at their respective ages, otherwise there'd be no story between them. Is there a good way to execute this narrative without coming off as predatory or even tabboo? I've heard many people say age gaps between two women together is weird. I've never thought so but I'd like more clarity from the people that think otherwise. Thank you!