Another stupid ethics question

[cts]

OK so today I'm 12-tabling on FTP and am sitting alone at one of my tables. Daliman sits down next to me and I know who he is by his screen name. He posts his blind, I have the button, I open to $70 and he folds his BB. He immediately sits out and types "$250 flip?" I don't do coinflips, never have with him or anything, and type "no i don't flip" or something. He then sits back in, posts his SB, and types "ok lemme get my blind back then." First, wtf? Why would I be supposed to give his blind back? I have a ton of tables open and don't have time to respond to his chat before the hand, I'm not sure if he posted or chatted first but they were close in concurrence. So he minraises to $40 and I go all-in with AKo. He folds and I show. He sits out and is really upset. He says something to the effect of "i minraised with trash bc i thought you would give me my blind back." Then he keeps saying how he's mad and disappointed etc, calls me and leaves a voicemail. Seems stupid to be making a fuss over $20 but I don't think I did anything wrong and he was seemed pretty upset, opinions?