Nice find. Oh, I remembered incorrectly, the Homura one comes with February's Comic Rex magazine which makes a bunch of sense because it's an alternate cover for the Guren manga. I'm sure you realised they make a pair.
Conspiracy theory, so take it with a grain of salt: Due to the sword giving her brain damage and leading to her changing her fighting style, Haruka has built a robot not only to help her in battle, but with daily life.
Then again, I could just be thinking about this too much.
Whilst the general situation is similar to the end of the game, what happens in that short manga is a just a joke. Very briefly: Haruka's under the influence of the final boss and she's saying "I'm just a doll". Homura refutes "You're not a doll. You're a walking obscenity!" <That's the joke. Haruka rages. They go back, Mirai's like "Where's my beloved Haruka~?" Homura says "Everything's fine" Haruka has the sword in her head and Mirai screams "It's definitely not okay!"