sydian cuntboy

Slight problem with the Sydian andromoprh (c-boy), it lets me try and have sex with his pussy even when my cock(s) are too big. Did some testing, I assume it's cocksize since Condensol enables me to bypass the error, and additionally, asks which cock to use. Without using Condensol, it doesn't...

Is there a specific mod to help him out with? I have gotten dicksprout and man up, and neither of them changed the 'give mods' thing on his victory encounter. What mod can you use for him?