Cool in manner (8)
I believe the answer is:
reserved
(Other definitions for reserved that I've seen before include "Booked, being unemotional" , "Unemotional; put by" , "Kept back" , "Uncommunicative, not extrovert" , "Shy; booked" .)
I believe the answer is:
reserved
(Other definitions for reserved that I've seen before include "Booked, being unemotional" , "Unemotional; put by" , "Kept back" , "Uncommunicative, not extrovert" , "Shy; booked" .)