My boyfriend was afraid I would think he's immature

I've been dating this guy at my school. The first time I went to his house his mom embarrassed him by telling me his Pikachu underwear was clean. And told me about his Pikachu obsession and proceeded to show me all his Pikachu underwear she washed. After that he made every excuse not to go into his room. Well I finally got to see his room and it was pretty empty. Like his bed was a mattress with a think blanket and no sheets. We would chill out in there. I left my jacket over there and came over while he was in the shower and went to look in his room. His brother said it may be in his closet so I opened it and out came so much Pikachu stuff. Like he had a million stuffed Pikachu's and blankets and figurines. When he came in his room he tried to explain himself but couldn't find the words and got so frustrated and started tearing up and I felt bad. I told him he doesn't have to hide his likes and hobbies from me and he said "You're just so independent and mature(I have a job outside of school and take care of my siblings) and I didn't want you to think I was immature and didn't want to be with me anymore". I gave him a kiss and we spent an hour putting his room back to how it originally was and I find his Pikachu obsession cute and at least he's an easy person to shop for.