Period. is everything you need to know about periods. PERIOD. Period. is a book for everyone; for children and adults, mums and dads, womb-owners and ex-womb-owners. There is no beating around the bush in this funny and informative book written and illustrated by Natalie Byrne, full of practical tips and advice from what a period actually is, to who and who doesn't have them. This book is a myth-busting must-read. For each book sold we will donate menstrual supplies to asylum seekers, refugees and those who can't afford them through Bloody Good Period.