If you did bite someone you'd get punished so it wouldn't even be worth it.
[ she recalls the time back when she was rabid and blood thirsty-symptoms of a werewolf bite- and how she killed three people before she was stopped. Even here, when her emotions and urges were brought to the surface through a change in the atmosphere, she came really close to hurting someone. ]
Feel better? [rose asks him as she unscrews the cap from her own bottle and takes a much needed swig before bringing it down again. she knows that she always felt relieved after she drank some blood.]