Eesh, people being so quick to judge. The sister definitely means well, but is downright oppressive in her affection for the FMC. It's a contrast to their neglectful, abusive mother and the MC's caring-but-passive family.
As for this apparently being different from the WN, I'm guessing it's to stoke a bit of drama/tension and draw out the arc a while longer. Have some conflict to further character interactions and give a stronger foundation. Or just to incite drama and keep readers engaged.
The suicide bait is frankly hilariously obvious. I'm guessing she plans to "disappear" by retiring and moving out so she's not overshadowing FMC just by existing. But MC and FMC will talk her out of it and resolve things in a way that's more bearable for everyone.
As for this apparently being different from the WN, I'm guessing it's to stoke a bit of drama/tension and draw out the arc a while longer. Have some conflict to further character interactions and give a stronger foundation. Or just to incite drama and keep readers engaged.
The suicide bait is frankly hilariously obvious. I'm guessing she plans to "disappear" by retiring and moving out so she's not overshadowing FMC just by existing. But MC and FMC will talk her out of it and resolve things in a way that's more bearable for everyone.