[ Karl's had - past differences with Rido. Enough to color his tone with mild dislike. Although Karl dimly suspects it's better to have the Pueblood on his side - rather than against him. ]

A wager. With a reward to be decided afterward. I wasn't given further details.

[ A shrug. ]

Knowing Rido, the reward involves blood-drinking. Or enslavement.

[ He's gotten a good feel of how the despotic Pureblood's mind works. ]