Forget is a minor, if irritating, ailment. There are far worse you'll have to deal with that will do more than 'unsettle' , but yes - for whatever reason, it can be knocked out of a person.

[God he cannot wait for the day Maruki is inflicted with whatever this bullshit world's version of Despair is. Oh, how he'll love to beat the shit out of him.]

I'm sure you won't have any issue hitting me as hard you as can. I look forward to doing the same for you someday. I'll do my best to avoid your glasses.