I need to know if this is wrong regarding my sister. I’m 18 and she’s 15, I’m small for my age so we’re not too different in size. Sometimes if she’s not about I’ll take her dirty underwear and masturbate with it on- it really turns me on. Is that wrong?
Yes! But you know that, it's why you asked... stop now before you turn into a sicko, get caught and run your family relationships.. You wont ever live it down...
In general society then yes it is considered wrong and imoral, however as @morrow said you already know this, so the question is did you ask to seek aproval from strangers or is there a bigger question in you that you dare not ask yet. Also just out of curriosity how do you know that your sister doesn't know?
Kind of the opposite- you’re right. I did know it was wrong, but I also know myself and I knew I needed to hear that from somebody else before I’d really internalize that it’s wrong and I couldn’t talk to anyone I know about it. I appreciate the frankness. Thanks.