the indispensable lightspot in Big Bang Theory ---- Dr. Rajesh Ramayan

Dr. Rajesh Ramayan"Raj" Koothrappali (Kunal Nayyar) is Howard Wolowitz's best friend, and yet another genius of the group; his name is usually shortened to "Raj". He is originally from New Delhi, India, and he works in the Physics department at Caltech, where his area of expertise is particle astrophysics. He lives in an apartment in Pasadena. As with his friends, he is mutually involved with and obsessed with science fiction and comic books in general, and is usually the one to propose various real-life questions derived from such works, such as the functions of the tails of the Na'vi in the film Avatar. He is also a fan of Harry Potter. Raj hates India, Indian food and Indian music, however, he does appreciate the Indian lullabies his mother sang to him and the catchness of Hindi phrases. Raj is a Hindu and believes in karma (reincarnation), but eats beef.

Raj is extremely shy around women, and finds himself unable to speak to or while in the presence of them unless he drinks alcohol, or he believes he has drunk alcohol. When Penny or Bernadette is around, Raj usually whispers what he wants to say to Howard or Leonard, who then repeats or responds to what Raj says out loud, although at times Howard will embarrass him by saying something completely different and inappropriate. Despite this, Raj has sometimes ended up in bed with women, leaving the other guys perplexed.Unlike his friends however, Raj has many quite feminine interests such as reading Archie Comics and Twilight and watching chick flicks such as Bridget Jones's Diary. A recurring joke in the series has people, including his parents and Leonard's mother, speculating that Raj might be gay due to his feminine interests and his close friendship with Howard, with whom he has arguments similar to those of a married couple. However, Raj has always stated that he is straight, but metro sexual.

He has had a crush on Penny, and secretly wrote love poems about Bernadette. Raj comes from a very wealthy family in India, and often communicates with his parents, Dr. and Mrs. Koothrappali, via webcam. He has a younger sister, Priya, who is mentioned to have dated Leonard briefly before the series timeline began and dates him again in Season 4, breaking up with him in Season 5. After making a brave speech about not being embarrassed to be single, Raj started seeing a very shy and sweet girl named Lucy. Lucy has many things in common with Raj including her fear of being in large crowds of people. In the season 6 finale, Raj finds he can now talk to women without alcohol, however he never stops talking.