Teaching one’s children about privacy and safety around masturbation is a great idea. In your case, there is the added issue of teaching respect for other people’s belongings.
Masturbation can be a healthy and positive way to express one’s sexuality. A parent can let a child know this and at the same time teach that we masturbate in private and we also respect other people’s belongings and do not involve them in our masturbation.
I would recommend a matter-of-fact approach. Simply stating the above in your own words. An example could be “I would like to talk to you about something important. It’s a bit awkward for me as we don’t generally talk about sexuality. Masturbation is a healthy part of one’s sexuality. Please be sure to do it in private and do not use my belongings.”
He may be embarrassed at being caught. You could let him know you are not trying to embarrass or shame him. You can be honest and tell him it made you feel uncomfortable, but you are not telling him not to masturbate, just to be respectful in how he does it.
You may also be concerned about his choice to use your panties. I wouldn’t jump to any conclusions about this without more information. Rather than meaning he is attracted to you, it may be simply that these are the panties he has access to. If you have other information that has you questioning this, I would consider consulting with a certified sex therapist.
Kinkly.com obviously is a great website for adults to learn more about sexuality. Scarleteen.com is another great website, aimed at teenagers. If you are looking for a resource for your boys, you could direct them there.
