German law is curious (and well-written) in that regard. "rape" is something an offence may be called but it's not a category of offence in itself. There's one single section covering sexual assault in various aggravation stages:
(1) Whoever, against a person’s discernible will, performs sexual acts on that person or has that person perform sexual acts on them, or causes that person to perform or acquiesce to sexual acts being performed on or by a third person incurs a penalty of imprisonment for a term of between six months and five years.
[...]
(6) In especially serious cases, the penalty is imprisonment for a term of at least two years. An especially serious case typically occurs where
the offender has sexual intercourse with the victim or has the victim have sexual intercourse or commits such similar sexual acts on the victim or has the victim commit them on them which are particularly degrading for the victim, especially if they involve penetration of the body (rape), or
the offence is committed jointly by more than one person.
Note the "at least two years" doesn't inherit the "up to five years" of the previous section and there's even higher minimums for carrying weapons, risk of damage to health, etc.
Only acts involving penetration are considered rape but it doesn't say by who or what, and even if the e.g. forced face-sitting didn't involve penetration it's still going to be on the same aggravation level.