Idol with normal person

@Panda I don't think she means a real idol + actor, I think she means the characters of the drama 

Star of the Universe
IF I didn't remember wrongly, Because of You
Bad Girls
Code Name : Jackal

i didn't understand what exactly you meant, so here are some dramas where characters are idols

• twenty years old (male lead plays fictional version of himself - gikwang of beast)
  
• one more happy ending (female lead is an ex-idol)
  
• star of the universe (male lead is an idol)
  
• exo next door (male lead plays fictional version of himself - chanyeol of exo)
  
• moorim school (male lead is an idol)

A Love To Kill
Trot Lovers
The Producers
The Eccentric Daughter-in-Law
Goong
Love Cells
Oh! My Lady
Full House (Thai version)

Heartstrings (he's not a full-fledged idol but he is a super popular musician within his campus)
Ho Goo's Love (female lead is a swimming star)
Fantastic (male lead is a famous actor and in my opinion this is a very good, underrated drama)
Uncontrollably Fond