According to the legal provisions, you can give permission for engaging in sexual actions once you are sixteen. This is stipulated in article 372 of the Belgian Criminal Code. Once you have reached this age, you may have sex with someone aged 16 or older.
When one of the two partners is younger than 16, the other person is punishable and can be prosecuted. A person under 16 is considered not to be able to consent to sexual actions. The other person can be prosecuted for indecent assault or rape, depending on the circumstances.
Indecent assault is an offence in which the person involved, in one way or the other, is forced to perform sexual actions without penetration (articles 372 to 374 of the Criminal Code). It includes forcing someone to undress, forcing someone to masturbate, touching the breasts etc.
Article 375 of the Criminal Code stipulates that rape is any act of sexual penetration of any nature whatsoever and with any means whatsoever committed on a person who does not consent.
Penetration literally means “enter into or force entry”. It is an offence if you penetrate someone’s body without this person’s permission. This includes French kissing: the judge may decide that the penetration of someone’s mouth with your tongue without this person’s permission is rape.
As mentioned before, you can consent to sexual actions once you are 16 or older. Prosecution of sexual actions with consenting people under 16 is possible based on the following rules:
Cruising is not an offence. It is not allowed to perform sexual actions in public places. This is an offence against public decency (article 383 of the Criminal Code). You can get a fine for it.