<human>: Could you distill the essence of the text into 1-3 sentences?

Just moved in with my boyfriend into a new apartment with very little storage space. He has about 10x the amount of things that I do, including clothes, books, workout equipment, etc. All of his crap is currently piled up along the wall of our new place and it's driving me insane. He has far too many things and whenever I talk to him about cutting down on his things he either avoids the question or gets defensive. 75% of his clothes he doesn't wear, the majority of the books he'll never read (I get it, I was an English major, I love books and I understand their sentimental value, but we're talking old textbooks and random novels I've never heard of and he's never read), 3 fishing rods and he's never gone fishing once since I've known him...the list goes on and on. I asked him if he could get rid of maybe one of the goddamn fishing rods, he said no. He even has a huge collection of a bunch of his childhood things, like children's books, that are just taking up space in our place. I'm a reading teacher and I asked him if I could bring them to my students to use but he flat out refused. I brought up the idea of a storage unit but he doesn't want to pay for one. Basically, he's stubborn as hell and hates being told what to do, but I'm at my wits end.  I just spent half of my day putting his books on bookshelves getting annoyed at how frivolous the majority of them are. I knew that if I put them away he would NEVER go through them and sort them out so I left the rest of them in suitcases. 

Maybe I'm the least sentimental person alive, but I feel like a lot of his things have to go, especially a lot of his childhood shit. In my mind if you don't use it, it has no purpose. How do I get him to get rid of all of this crap? Is there a better way to go about this or bring it up, or am I being cold and unreasonable?
<bot>: just moved into a new place with my SO, he has a lot of things that he doesn't use that he won't get rid of. How do I get him to clean through and cut down on his things?