Genshin Impact: Asmoday is Paimon Theory
*Includes spoilers for the 6.5 World Quest, reblog & save post for later after you complete it if you want to read and haven't finished it*
My theory on why Asmoday kidnapped the Traveler: Asmonday was bored. Let me elaborate: Asmoday is the Ruler of Space; she existed primarily in the Realm of Space where time is eternal, and no one can die, which includes herself as well. Drifting in eternity forever, all she could do was rule over her domain, and watch Teyvat from afar. So one day, she had an idea; what if she introduced unknown variables into Teyvat? The unknown variable are the Traveler, a Descender who could influence Teyvat in ways that other beings living there cannot. Now for the first time in a long time, she had no idea what was going to happen next, and had excitement in her life again, saving her from endless melancholy.
Asmoday is Paimon??? theory: This is not certain at this time, however I cannot rule out the possibility that Paimon & Asmoday are one and the same. "But, why would she separate the Traveler from their Sibling and send them down to Teyvat as a Descender?"
Asmoday was bored drifting in endless eternity & melancholy, so she wanted to do something new that she had never done before. She thought to herself: "What if I join the Descender on their adventure?" Instead of watching Teyvat from afar, she would get to explore it herself with the unknown variable that she had created. Asmoday created Paimon as an alter ego (whether she's lying or she erased her memories in the Temple of Space) and went down to Teyvat to meet the Traveler and join them on their journey.
"Why did she never tell the Traveler who she really is?" I can think of two possibilities: 1) She felt guilty for lying. Asmoday (Paimon) genuinely began to enjoy her adventure with the Traveler and she started to feel something for the first time in ever, but because of this, she also began to feel guilty. If the Traveler found out she separated the Traveler from their Sibling, would they hate her? The thought was unbearable to her. She never wants their friendship to end! So, she kept up the disguise that is the Paimon we all know. 2) Asmoday gave herself amnesia. We know it is possible for the Temple of Space to make one lose their memories, so what if Asmoday found a way to do it to herself? She wanted no way to be found by her sisters or recognized as Space by anyone else upon entering Teyvat, so she gave herself amnesia, making herself a blank slate. Then, she became Paimon, and the rest was history.
There's no way to know for certain if any of this is true, but I think it'd make a lot of sense if it were.