Alright, obligatory stuff first; I'm using a throwaway account obviously

So first of all I'm going to give you a bit of backstory; as seen in my post history, I recently left an overly-toxic friend group full of people who mocked me constantly(read about it there if interested)

Now, I knew somebody in that group who I'm going to call K for the sake of this story. Now K, back in last year was kicked out the friend group due to a large argument between me and him, I eventually felt bad and hanged out with him until my friend group added him back, in their words for the 'sake of having me back'.

Now, this group was a comedy group and often mocked it's members, however, K always targeted me and used anything I said or did to use against me as a joke ( I have ASD and felt really uncomfortable by this and asked him to stop); I would leave because this never stopped

After I left, I at first treated K like a really close friend; until I found out he was being threatened to go against me or get kicked out. After that point, I get more news from friends about him saying stuff about me behind my back such as \`I'll come crying back soon\`.

Since then, I ignored his message every day saying \`Hi ACAG\` until one day I snapped; messaging him that we're not friends and that friends don't talk about each other behind their backs

Next day, he was **fuming**; talking to another member in the group angrily confused why I blocked him, not having a clue. I then say to him in the first lesson where we are next to each other, to move away from me in other classes or I'll move myself . He seems hurt but nods his head.

However, when I get into the lesson, he decided to sit in the exact same spot; when I confront him about it he says \`I prefer it here\` and to move myself.

Then comes today, another member of the group T, joins a discord server I'm very active in; and messages me out of the blue(I unfriended him) and this server was the same server I added K to month ago to show him where I'm mostly active. I **freak out** convinced that K sent him it. According to T he researched a game jam I took part in to find the discord. 

Therefore, tonight I asked T to leave and he agrees without question and argument ( T hasn't bothered me once ). However, when I tried to ask K he refused until he finds out the real reason I stopped being friends with him

*I'd never actually given him a reason why*

I try to explain what I'd heard and he just carries on probing for details, not believing me until I give up and say \` Because I'm sick of you, the way you act etc \` and \`I genuinely dislike you\`. It works and he ends up leaving the discord saying that's all he's wanted and that he will move away from me in physics now

What I'm wondering is AITA for ghosting this friend; removing him and lying about why?