Eldest son of Mace Tyrell and Alerie Hightower, born at Highgarden and bred to be Lord of the Reach after his father. At sixteen he rode his first tilt against Oberyn Martell of Dorne, and the Dornish prince's lance caught his courser so foul that the horse fell on him and crushed the leg beneath, leaving him lame ever after. Where the Reach took offense at the Red Viper for the maiming, Willas would not, and the two have traded letters of horses and hawks in friendship every year since. He keeps to Highgarden with his books and his hounds, flies his hawks at the brookside, and is reckoned the finest breeder of horses in the Seven Kingdoms, his stables prized for sand steeds out of Dorne and chargers got upon his own dams.
When the Lannisters set Margaery Tyrell beside Joffrey in Sansa Stark's place, the Queen of Thorns and Lady Olenna laid a second snare to spirit the elder Stark daughter south to Highgarden and wed her to Willas, that the rose might claim Winterfell through her; Lord Tywin caught wind of the scheme and, on three days' notice, married Sansa to his son Tyrion instead. Willas remains heir to Highgarden and to the great green span of the Reach, a quiet scholar where his father is loud and his grandmother sharp.