I have a question about this molecule (bodipy) and B-N bonds

[Spathi]

I have a question relating this molecule (bodipy) :

How do modern empirical models in chemistry explain the B-N bonds in this compound? Maybe we should consider this bond as having bond order = 0.5?
The same story with metalloporphyrins.

 

[TeethWhitener]

Why 0.5? What’s the problem with 1?