What should I do, my significant other has kept half naked pics and voicemails of his ex. i feel they need to?

Talk to him and tell him how those pictures and voice mails bothers you and see what he says. I think it's totally inappropriate and a bit disrespectful to you.

This man still holds a torch for his ex. If a person is unable to let go of that sort of memorabilia and focus on your relationship, it is not worth your time. There is emotional or sexual connection he still has with this woman, or likely both. I had pictures in a keepsake of an ex boyfriend, and my boyfriend discovered them and said he didn't like it that I had them. I respected his feelings and was able to throw the pictures out, no problem. However, it sounds like he is keeping these things so he can reflect on what he had with her when you are not around. You don't want someone who is only giving you 50% of his heart and mind. Move on.

Make an ultimateum, what he is doing is disgusting!

WHY is he keeping them? I mean honestly, if he is with you then he really does not need old pics of his past conquests...or does he? I mean really, how insecure is he? I would drop this loser..you can do better.

does not need to keep them
ask him nicely to can them
if he does not
there may be a problem

there is no reason for them to keep them if they are happy with you. perhaps they are not over that other person. do you really want to be second best and not first choice?dont you think you diserve to be some ones first choice and not just a pasafier for the other while they fantisize about some one else? im sure you already know the answer you just need aferment. dont nag or cut them down for it ,,the heart wants what the heart wants, just find your hearts disire as well, and wish the other great happiness, and go find yours.

Are the pictures and messages new, or are they from the time they were together in the past? As long as they are old, then there is no reason for him to get rid of them. His past is his to own and keep, just like yours belongs to you. Like it or not, they had a relationship that left a mark on him, and it's not fair (or healthy) to expect him to "forget" it ever happened.