Fencer

A skill that will make sure you never touch a on a ship.

No, really, having this skill with the knife makes you more powerful than even a when it comes to attacking others, meaning any rational human will ensure the knife stays as far as possible from you. However if you are a trusted human yourself, you might be able to borrow the knife to deal with any suspicious and/or rampaging Mush, just don't be surprised if you're asked to drop it afterwards. Once the mush are dealt with, this skill can still have utility if there are no s alive, as extra combat strength during expeditions always helps.

In any case, this is likely a skill you shouldn't bother choosing until you are ready to utilize it.