<human>: Can you succinctly summarize the text in 1-3 sentences?

Since my boyfriend and I have graduated from grad school, we have (very gratefully) been living with his parents to save up for moving out. My boyfriend's sister does not live at home, and lives a few hours away. She visits about once a month.

Since my boyfriend and I are living in his childhood bedroom, there isn't much extra space for our stuff. A lot of it is in storage. The closet in particular is really small, and we both have causal and work wardobes. Because of this, I've been keeping some of my clothing in bf's sister's old bedroom in the closet, which is next door. I thought this was totally fine, as she told me that she wasn't using the space anyway and to go ahead. 

Yesterday I asked my boyfriend if we could put the ironing board in her room as well, since it takes up so much space in our room. He got frustrated with me and said no, and that I shouldn't be keeping so much stuff in her room. He told me that she has been complainig to their mom about my storing my stuff in there. I ask if I could just talk to her about it, and he laughed and said no. He said its just how she is and to keep my stuff out of her room. I tried to explain why I felt like it wasn't a big deal to keep an ironing board in her old room and that she would get over it (probably not the nicest thing I've ever said) but he was adamant that I was in the wrong.

I think this is pretty silly, as she doesn't live there, doesn't bring much home when she visits, and told me she didn't care. Am I being rude by keeping my stuff in there? Is it okay if I talk to her about it?
<bot>: Bf's sister doesn't want me keeping my stuff in her old childhood bedroom while I live with bf's parents - okay to keep my stuff in there/talk to  her about it?