Taken from the guide:

• Get the enemy (and audience) horny enough (60 lust): infinity blade XII (+3 ATK)
• Let the battle last 10 or more turns: force glove (+1 DEF)
• Win by reducing the bull’s HP to 0 (not by lust!): void armor●modified (+1 DEF)

Doing all 3 also gets you one of the scenes; doing the 10 turns, 60 lust BUT losing gets you the second one (and the full reward anyway).