The weirdest player behaviour case i've ever encountered - stalker lee sin

So before i start off, this isnt a post asking for someone to be reported or banned. I'm simply sharing my account of the strangest encounter i've ever had during my many years of league, and wether this sort of behaviour could be considered reportable or not.

So my last ranked game i got matched with two players that had played together before or something. Apparently out Lee sin had tried to add our support, Alistar, and Alistar had declined.

That's not weird. Within a couple seconds of the lobby i could tell something was up with this lee, however.

He was straight up obsessed with this alistar. He kept calling them Mao (I guess they played maokai last game?)

and here's the unsettling part

He wouldnt stop chatting to this guy. He just kept on chatting and chatting and chatting, asking where alistar here was going for their vacation (apparently they're going on a road trip in a couple days?) and asking if they live in town x. He wouldnt stop this THROUGHOUT THE ENTIRE MATCH - he kept asking if alistar lived in town X, over and over and over. When Alistar said he lived in another town, lee said he didnt believe him and kept asking the same question.

And then halfway through the match as we began losing (and im not saying its because lee was sending a chat message every 10 seconds) it got worse - lee started asking about Alistar's real name. I have encountered all kinds of toxicity in this game, i've encountered the summoner spell cooldown reduction exploit back in Season 2, i've played against golden age Riven as well as feral flare Udyr. That old "no cooldown blade of the ruined king" hack? Still got a recording saved on my PC.

But this is the most unsettling thing i have EVER encountered in all my years of league, and perhaps all my years of gaming overall. This was was OBSESSED with our support to the point of distracting everyone on our team and spending the entire match trying to get to know this player personally. His questions just kept getting more and more personal over the course of the game, i had to mute him to stay focused.

Lee wasnt necessarily a bad player, either! He just spent the entire match chatting rather than playing, so once he fell off, he fell out of the game completely.

Would you consider this offensive behaviour? Not only was it extremely unsettling (downright disturbing) but it was obviously bringing poor Alistar (and his premade mid laner) a lot of discomfort.