We've all seen the male villain/bad-guy who goes good for the girl, but what about

I know its not likely, but anyone know any shows with a female villain/bad-guy who goes good for the guy?  

On a completely unconnected request:

Anyone know any shows that feature a mentally-challenged character as a secondary main character or a larger minor character?  I know I've seen some with a mentally challenged character as the lead (like Ataru), but I was wondering if anyone knows any with them as as a major secondary instead.  Maybe something like the main characters sibling, or the sibling of someone the main character knows/care about, something like that

On a Post Note: These are requests for 2 different shows.  Any recommendations do not need to have both situations 

 Czakhareina:

1. Anti-heroine dramas is kinda hard to find, but maybe....

• Miss mermaid
• Yoona's street
• Others, though i dont really think its what you are looking:  Spy Myungwol, Suspicious Housekeeper

2. Mentally challenge big supporting character though they are mostky for long daily/weekend dramas:

• Can you hear my heart - the FL's father and he had so much big role in the drama. I became a big fan of Jung Boseok because of this
• Smile again - ML's mother and she has her own story arc
• Gloria - FL older sister with her own story arc
• Shining inheritance - FL younger brother, he was a minor character but he was definitely awesome. 

Thanks, some of these definitely look interesting.  While it may not be the "anti-heroine",  Spy Myungwol looks pretty interesting

For your second request (mentally challenged):

• +1 Can you hear my heart
• ToGetHer 
• I'm Sorry I love you (she's the male lead's sister)
• Gomen Aishiteru (she's the male lead's childhood friend, this is the japanese version of I'm sorry I love you)

 JoanneSmith:

Just Between Lovers, that just finished wrapping up, has a prominent supporting character who is mentally challenged.   And i loved the character.   

Was gonna recommend the same drama. Sangman <3.