As far as I know Grian has never said anything about not wanting/liking to be shipped.

I have heard rumors that Grian liked a piece of Grumbo fanart. I don't know if this is true or not and have looked on Twitter to see but I did not.

I don't want to say this didn't happen but take it with a grain of salt.

Another occurrence of Grian being ok with shipping was the Grumbot thing where they were dads. I know this wasn't really a shipping thing but I thought I should put it in.

Note: As of now he is married

If you have anymore information regarding this please dm me or leave a comment.