The Anonymous Friend of the Crapulous Man

Plutarch, Antony 9.4

λέγεται γοῦν, ὡς ἐν Ἱππίου ποτὲ τοῦ μίμου γάμοις ἑστιαθεὶς καὶ πιὼν διὰ νυκτός, εἶτα πρωῒ τοῦ δήμου καλοῦντος εἰς ἀγορὰν προελθὼν ἔτι τροφῆς μεστὸς ἐμέσειε, τῶν φίλων τινὸς ὑποσχόντος τὸ ἱμάτιον.

They say that after feasting the matrimony of the mime Hippias and gorging himself on wine for the whole evening, he (Antony) was called to the forum early the next morning by the citizens.   He showed up, still stuffed with such 'nourishment', and puked as his friend held out his toga.

That is a true friend.