If they're on an english site they probably want to learn and practice english, otherwise why not post on a Japanese site instead.
So it might be a good idea to provide simple english to go along with your Japanese when reply to this guy.
Besides I personally have no evidence he actually is Japanese as this is the only thread I've seen and I just hear people saying he is.
Because let's face it, most people visiting this site will not know enough Japanese to know if someone is faking it or not. I can speak and write a small amount of Japanese.
I can understand what everyone is trying to say except this guy here:
>>525145, his sentences are too convoluted and full of I's and 'yous' for me to know what's going on. (My apologies.)
But yah. Everyone else on this site is english too, so translating your posts for others to read might also be a benefit.