This is a relationship between the characters of Twelfth Night.
Sebastian is the twin borther of Viola.
Antonio is Sebastians friend
Orsin is madly in love with Olivia, but the feeling is not mutual.
Viola is madly in love with Orsino.
Cesario is the messenger for Orsion.
Orsino thinks that Viola is a man (Cesario.)
Maria is the gentlewoman of Olivia.
Sir Toby and Sir Andrew are best friends
Fabian is Olivias servant
Maria likes Sir Toby as a friend
Feste is Olivias fool
Maria hates Malvolio
Malvolio is the steward of Olivia
Olivia is Sir Toby’s niece
Sir Andrew is the suitor countess to Olivia
Valentine is the courtier of Orsino