Responses

Healing factor was mentioned in the earlier chapters.
Regarding the blood, well, that what makes the scene sexy. It also carry subtle meanings such has burden among espers, his condition, etc. It makes the scene more meaningful, considering that this has heavy themes. It's about interpretation and analysis.
For someone properly trained in medical care, you sure don't look like it. With all those bloody wounds! You're not very convincing ( ̄∇ ̄")