Big brother???

Ok so I've read a few post on here talking about big brother instead of daddy. Anyone into that? I think I might be. I can't bring myself to think of my bf like daddy. I never had a good relationship with my dad and that's just a touchy subject. But big brother seems a little different for me. I've always had an interest in step sibling stuff. Never done it lol no step siblings lol but the idea of someone older and smarter who loves and cares for you but not parent wise. If that makes sense. I've always had a fantasy about an older brother or step brother who would sneak in my room and teach me about sex or take advantage of me while still caring and loving for me. And I've even thought of my bf like that a couple times. I'm terrified to tell him that even tho we're both interested in the step siblings idea. I want to role play with him like he would sneak in our room "my room" and whisper to be quiet so we don't get caught (cause we live with his parents) and then take advantage and "teach me" things. Like it's the first time. Idk why I'm like this but the idea is so hot. And he's a few months older than me and he's the dominant one in the relationship anyway and teaches me all kinds of things. I love learning from him and having him guided me. Following his lead basically. He's really smart and I would love to play like a teenager with an older step brother or brother who decides to teach me a little more than just life lessons lol 😍