
Who is Who and What is What based on their respective personalities, not on the basis of relationship.
Bani = Draco Malfoy
Charming but overly-pampered by her community gives her a false sense of entitlement and despite of being at the right place to pull strings, incapable to use her resources properly (and don't criticize because I love Tom Felton)
Gaurav = Sirius Black
Even though he is right on occasions, he lacks conviction. Forgot enemies, he cannot even convince his friends.
Rahul = Remus Lupen
Though people look up to him for wisdom, he has problems of his own. On the full moon night, he starts frying jalebis in tattis.
Lopa = Fleur Delacour
Being beautiful is the job.
Rohan = Fred/George Weasley
Good looking, confident but morally upright, instigating people is his favorite hobby
Karan = Gilderoy Lockhart
Loved by everyone specially women because they don't knows who he truly is. Despite of boasting a lot, failed to defend himself in actual fight.
Mona Lisa = Moaning Myrtle
Though she is not haunting an actual toilet in the house, yet she is giving that vibe as if she is dead and have to live in a toilet now.
Manu = Gellert Grindleward
He wants power and he will go to any extent to get it. Only powerful people can control him.
(No he is not the toilet that Mona is haunting)
Manveer = Ronald Weasley
Always the second best. His temperament is his biggest problem.
Lokesh = Mr. Weasley
Have fascination for things far from her reach and end up not achieving realistic objectives.
Babaji = Peeves
He only wants to create trouble to have some fun and get some attention.
(Those who have read the books know him, those who haven't, he is a 'noisy poltergiest')
Salman Khan = Severus Snape
Loved and Lost, but still try to help people yet unable to control his tongue end up being a villain in everyone's eyes.
Bigg Boss = Albus Dumbledore
Despite of knowing everything wants people to figure it out on their own and learn something about their innerself.
Priyanka Jagga = Dementor (Suggested by Angel-From-Hell)
She definitely sucked happiness from her environment.
Feel free to add suggestions. 😛