As long as it's all in your head.

It isn't the matter of gender but I prefer to not ship anyone with anyone irl. Fictional characters I'm okay with but somehow it feels kinda insensitive to ship people with others when we don't know how they feel about that person romantically. Many fans ship idols with one another, even people they might consider as family. If I knew someone shipped me with someone I really like being close friends with, almost family, I would feel weird.

For me that's a big clean divide between fictional characters and real life. But as long as it stays in your head, I don't see why not.