My younger sister is the big villain

Reborn in the fantasy world, Qin Jiuge became the son of the Changsheng Qin family.
Looking at my own superior background, could it be that this is a familiar villain plot?
By the way, what about the system?Don't they all come with their own system after rebirth?
[Congratulations to the host, awakening the strongest villain..]
Qin Jiuge: The strongest villain! !What a dick!
【The strongest villain support system】
Qin Jiuge:? ? ?
[The system binds the host's sister as the auxiliary object by default, come on, host, work hard for your sister! 】
Qin Jiuge: .. the system are you messing with me?In this way, am I not a villain's dog?