People get possessed all the time.

No one would help him get to the bottom of Kerberos, and it had all reached a breaking point when Iverson threatened to terminate Keith’s scholarship if he kept snooping. So Keith got what he came for, the little black book no one was ever meant to find, and stopped snooping. Because now, he’ll have someone else to do all the snooping for him. The situation isn’t ideal, Keith thinks as he slits his palm open and methodically draws the pentagram on the floor, placing the necessary items one by one into each point of the star. But considering the circumstances, he thinks he’s done alright for himself. More importantly, for Shiro.

Sam and Dean have always been oddities among the dragonriders; the youngest man to Impress a Bronze dragon in a hundred years and a boy who turned his back on the riders to become a dragon healer instead. But when fate steps in and chooses a far different path for Sam, the brothers and all the Weyrs of Pern will have to come to terms with much greater changes in their traditions.