1. Chastity
Alecto always wanted to be the perfect pureblood girl the one who always listened to her parents and was rewarded for doing what she was told. So when her father had said no sex until marriage she had listened to the end. She had never laid in bed with a man, and to the day that was the only virtue she had left. Being a death eater meant killing, plundering, and doing things that no human should do.
Alecto was only doing the right thing the pureblood thing. Chastity happened to be there for she never married. She watched as foolish women like one of her very own Bellatrix Lestrange tried and failed to get themselves with men. Alecto had better things to do, and she wasn't going to please the Dark Lord by sleeping with him. The men of the death eaters saw it as there manly duty to ravage bodies. Alecto hated to watch as the women and sometimes even young girls squirmed against her colleagues and once even her brother. It made her sick the business of sex. Now it not only had become her fathers' wishes but her choice to remain virtuous.