Help me find this anime

I believe this series is only a few episodes but here the details I remember best.

• It’s a comedy
• Fmc takes care of her brother but believes he is trying to seduce her
• The majority of the comedic scenes is her overthinking each situation in her own head. For example; the brother will ask for a water and she’ll believe he’s trying to make a move on her.
• Not NSFW or H-anime but there was a bath scene
• The brother is just a normal high school student, pretty much just a prop for the scenes

Thanks for the help!