Ok im 15 and a guy. I started to masturbate at 14. But for the last few months i really started to do something kinda out of the ordinar. I don't why i been doing this but its like this. When i come home from school my parents sometimes go out and stuff and they trust me to be alone. I have a sis a lot of times they take her to cheerleading practices which leaves me at home. Once or twice a week when im home alone i start to have sexualy urges and like to masturbate. I started to sneek in my sis room and get a pair of her thong panties she leaves laying around its usually a pair she been wearing and hasn't been in the wash yet. I usualy sniff the crotch area for sexual arousal and head off to my room to masterbate until i cum. I been doing this for 6 months is this kindy strange or im i ok.