I'm sure that the top panel on page 15 isn't ominous at all. Shadows covering half her face while giving a congratulations that don't really match her expression totally isn't an indication that she's actually depressed about her childhood friend finding someone that isn't her. Nope...
It really was just a series of asspulls for no reason. When she was like "wow, that was such a tough fight! i almost died!" I... Didn't get that feeling at all.
I honestly doubt that the arm is part of her standard equipment. It seems more of a way to take Tugernanner on a covert operation than something she's used to. Like, she's catching the baby and then she looks over and sees that Nana mangled the guy behind her. She looks genuinely surprised...
This is almost certainly a flashy interest hook before multiple arcs of "how we got here."
Even the "prologue" mini chapter had Wendy swearing vengeance on Junko, Hinako, and Elis. Whereas here she's chilling with two of them.
We don't know. Kyou clearly has a connection to Kiku from before Kiku woke up from cryo stasis. But the manga has left the details of that relationship an ongoing mystery.
"he was attacked by a chihuahua"--oh, this is a gag overrea...
"It bit his carotid artery"--oh. OH. He's lucky to be alive.
Also:
He learned how to "forsake his humanity" from the master, huh?
Starting to warm up to someone, seeing their bananas behavior, and going "wait, what was I thinking?" is a pretty common gag joke. I'm pretty sure it's come up in this manga before. Multiple times probably.