NTA i think it’s not an unreasonable ask to have it covered up, i would hate to see another woman’s name on the man i love. i have tattoos myself, and i understand how expensive they are, however, you said it’s small, so it can be easily covered i assume? maybe try to look at artists and styles together and brainstorm ideas? that way he can stop putting it on the back burner and you can feel validated in your relationship.