Grant West, also known as Rapier, is "Wolf" West's's second son.
Jonathon "Wolf" West cheated on his wife at least once with an American woman, concieving Grant.
As he grew up, Wolf saw Grant's potential as a soldier, due to his loyalty and obedience. However, Grant grew up hating his half-brother Jack West Jr., as Wolf saw Grant only as his second son, and believed that if he killed Jack he would become the better son in his father's eyes.
He was originally a part of Delta, gaining his call-sign Rapier, before being seconded into the CIEF under his father's command.
A cold and compassionless person, Rapier is the ideal soldier in his father's mind. Despite the apparently endless pride Wolf seems to feel for him, Rapier knows that he has more respect for his older brother Jack, and it is this fact that makes him burn inside.