Not very in-depth, but these are the guidelines for Virus EXP/Zenny rewards.

500 HP Max
5 AP Max
200 Attack Damage Max
200 Aura Max (Optional)

EXP Award (rounded down) = (HP + AP(100) + DMG)/60
Zenny Award (rounded down to nearest five) = (HP + AP(100) + DMG)/2.4
Add +1 EXP/+15 Z per 10 points of Aura

20 EXP max for a Virus
500 Z max for a Virus