I have to agree with Jimmy on this one. The boyfriend had it coming. I don't know the whole story. I don't really care. I just put myself in the father's shoes. Just because some man made law says it's ok, doesn't make it so. At least the father had the "balls" to take action. Bread knife was a nice touch. I might of used kitchen shears or a hobby knife and then a hot iron to cauterize.
Seriously, though, something would have to be done. Whatever you could get away with. You can't let some 57 year old, immature, sick fucker get away with porkin your teenage daughter.