yeah i looked into all the executions for vestal virgins once and not once did they state it was for messing with other vestals or masturbation or anything like that. they considered them 'daughters of the state' so having sex with any man (generally only an alarm when someone becomes pregnant) was considered incest and worthy of execution. wild shit. and since they were 'the state', they could free slaves. and generally if something super bad happened in rome theyd come under scrutiny and investigation because if a vestal virgin became unchaste it would invite calamity.