In a novel written in English, police in a large city suspect a certain unkempt young man, the protagonist, of being a vagrant, and they have trouble with lots of those converging on that city. His respectable-looking acquaintance says he's a young friend of his from the country and he's become a bit confused, and assures the police officer: "I'll be responsible."
A translation into German that last sentence is as follows:
Ich nehme mich seiner schon an.
Among the various translations of the verb "annehmen" at dict(dot)leo(dot)org, one finds this:
sich[acc.] jmds. annehmen
to minister to someone
So "seiner" seems to be a possessive adjective qualifying an understood feminine singular noun in the genitive case. What would that feminine singular noun be?
And are there other verbs having genitive complements of this sort?