Is it a large or very visible tattoo that you're thinking of, or is it small and relatively discreet? It is absolutely your body and your choice, and he has no right to impose his opinions on what you do with your body, but he also has the right to not feel attracted to you if you get one, especially if it's huge, glaring, in his face, and/or impossible to overlook. I think most people could get past a small, hidden, or fairly discreet tattoo on a partner, even if they're not a fan of it. But it would be much harder for him to accept or get past or overlook it if it took up your entire back or chest or torso or something. Not impossible necessarily, but harder.

My ex husband was very anti tattoo. (He was also anti unnatural hair colors and body piercings, but those were easier for him to accept since they didn't have to be permanent.) He just hated them, thought they were trashy and unnecessary and tacky, felt they were ugly, just hated them. I'd always wanted one, but wasn't willing to get one until I was very sure what I wanted and that I wouldn't regret it. At some point, I decided I really wanted a tattoo of my cat's paw prints. I sat on the idea for about a year, making sure I would still want it later and bringing it up for casual discussion every now and then. The most he ever changed his mind was eventually grudgingly admitting that it wasn't the worst idea for a tattoo ever, and could possibly be considered cute by some people, though not him. We had discussions about how if I really wanted it, I didn't need his permission, but I did want to make sure he felt heard and respected and considered, even if I ended up doing it. Finally, I decided to do it. I let him know when I made the appointment for, how big it would be, where I was having it done, and that I didn't expect him to be excited, but I did hope that he cared enough for me to get past it and not make it a bigger issue than it was. He was less than thrilled, but it gave him time to get used to and accept the idea.

When I had it done (it's two paws about an inch each on my right hip), I showed him when I got home. I could see the dread in his face. When he saw it, he seemed relieved. He said it wasn't nearly as bad as he thought it would be and it was kind of cute to think that our cat's paws were a permanent mark on my body. Over the next few weeks, he became increasingly enthusiastic, even sometimes poking at or petting them with a finger. I asked him about it, and he replied that it was a part of me, and he loved me, so he grew to love it too. He ended up being rather fond of the paws.

I'm sure it would have been different if I'd just shown up one day with a tattoo and not warned him first or if he had expressed his dislike of them and I'd told him to go fuck himself because I do what I want or if he had felt unheard or not considered in the decision. But I'd heard his side and considered it thoroughly, and he knew I got it because I really wanted it, not to spite him. He also knew exactly what to expect, and he never felt pressured to pretend he loved it if he didn't. We were both careful to consider and respect the other person's side and point of view, and I think that made the difference.