(1).Rape:

S118(3) Crimes Ordinance (Cap 200)：A man commits rape if—
(a)he has unlawful sexual intercourse with a woman who at the time of the intercourse does not consent to it; and
(b)at that time he knows that she does not consent to the intercourse or he is reckless as to whether she consents to it. (Added 25 of 1978 s. 3)

(2).Indecent assault

Section 122 Crimes Ordinance (Cap 200): Indecent assault

(1)Subject to subsection (3), a person who indecently assaults another person shall be guilty of an offence and shall be liable on conviction on indictment to imprisonment for 10 years.
(2)A person under the age of 16 cannot in law give any consent which would prevent an act being an assault for the purposes of this section.
(3)A person is not, by virtue of subsection (2), guilty of indecently assaulting another person, if that person is, or believes on reasonable grounds that he or she is, married to that other person. (Replaced 90 of 1991 s. 7)
(4)A woman who is a mentally incapacitated person cannot in law give any consent which would prevent an act being an assault for the purposes of this section, but a person is only to be treated as guilty of indecently assaulting a mentally incapacitated person by reason of that incapacity to consent, if that person knew or had reason to suspect her to be a mentally incapacitated person. (Amended 81 of 1997 s. 59)

(3).Child victim

Section 124 Crimes Ordinance: Intercourse with girl under 16

(1) Subject to subsection (2), a man who has unlawful sexual intercourse with a girl under the age of 16 shall be guilty of an offence and shall be liable on conviction on indictment to imprisonment for 5 years.

(2)Where a marriage is invalid under section 27(2) of the Marriage Ordinance (Cap. 181) by reason of the wife being under the age of 16, the invalidity shall not make the husband guilty of an offence under this section because he has sexual intercourse with her, if he believes her to be his wife and has reasonable cause for the belief.
(Added 1 of 1978 s. 6)

In HKSAR v. Choi Wai Lun[2018] HKCFA 18. CFA held that the true interpretation of section 122(2) is that, the presumption has been displaced so that the prosecution does not need to prove mens rea as to the girl’s age, but the accused has a good defence if he can prove on the balance of probabilities that he honestly and reasonably believed that the girl was 16 or over.