Blame the lord for that one.
It all happens on EV24.
Kurt has put under arrest due to false charges.
To free Kurt before his execution, Arika made a deal with the lord.
The lord puts a clitoris curse on Arika and a magical ring that makes her lose 'something important' (as in; her love for Kurt) everytime she ejaculate her clitoris semen.
The lord will free Kurt, regardless whenever he wins or loses, but the stakes are higher for Arika.
If Arika can put up with it for 3 days, the lord removes the clitoris curse with no strings attached and there will be no further demands from him.
But if Arika gives up before those 3 days are up, she will be a Sex Knight for a 20 days contract and the curse (clitoris enlargement only) remains.
3 guesses on how that ended.
I have explained this twice already, but...
So while the aphrodisiac are partly to blame, the size of the lords dick and stamina in bed won her over, as Kurt so small it's no contest. Typical Takeda Hiromitsu plot.
Alpha male (the lord) vs beta male (Kurt).
No, that's the NTR path, as it's happening before the remodeling by the goblins.
There is no sex scene/event on the good ending as of now, but maybe TH will make one eventually, when he stars making the endings of the others first.
Go back to page 526 and it's there.
robus77 is your hero there.