[Menarker]

His affinity to saving devil users just stems from the fact that he is a fishman and it gives him a competitive edge in getting hired as a mercenary. His "affinity" is due to CAPABILITY not desire.

Fact 1: Devil Fruit users are highly valuable members of any crew or army due to their power and their overall rarity. (The powers are one of a kind. You can never find another fruit of the exact same type. That fruit user would have to die and then the tree that sprout it will grow another one only when that previous user died, if my memory is correct. Thus there can never be another person at one time with the same capability that can be hired.)

Fact 2: Devil Fruit users can't swim and they become useless in deep water.

Fact 3: Typical humans may not have the strength to dive in sea water, reach the target and pull them back up INTO the boat with their railings high above the water itself, especially if the water is torrential or if they are in a fight and moving the ship a lot. If the crew in question is mostly devil fruit users, very few people can actually volunteer to help without getting in trouble too. Cyrano actually CAN do that, so it's a plus to his resume.

Fact 4 (Which I neglected to mention in more detail): Cyrano doesn't care about devil fruit users either way. He operates like a mercenary. If they are on his side, his ability gives him a great chance to save something valuable for the crew (A plus for getting him hired). If a devil user is a foe though, he has the sword to protect himself or anyone else from them.

So long story short, the two entirely different things. He could save ANYONE who falls off the boat, but because Devil Fruit Users are so valuable, anyone who is a strong good swimmer is worth more as a crewmember. He doesn't actually care either way about Devil Fruit users specifically. But given how dangerous they CAN be, having a weapon that can stop them is valuable both as a mercenary and for healthy self-interest. If a devil fruit user (or anyone else drowning) is on his side and in trouble, it's in his interest to help them if the situation allows it for the sake of payment. If a devil fruit user causes him trouble, he'll fight them without a worry.

So really, he's not helping them without question, but more like he's doing any sort of lifesaving because he honors a contract and expects to do the job well so he'll be paid. Anyone who attacks him, however, faces his sword.

Also helps that seastone removes the power of a Devil Fruit user, which is good for capturing if such a request is made instead of killing. (A bit harder, but at least he has a sporting chance.)

Is that reasonable?