Monster unaffected by Spell/Trap vs. Monster given protection via Spell/Trap

Question

If a monster's effect makes it unaffected by spells/traps, what happens if it attacks a monster protected by Waboku or something? Does it still get destroyed?

Answer 1

The thing here is that the one unaffected by spell/traps is your monster.

However, that does not make your opponent's monster unaffected by spell/traps.

Protecting your monster from spell/traps does not negate a spell/trap card that affects your opponent's monster.

You could, however, make your opponent's monster unaffected by spell/traps (for example targeting with whatever effect made your monster spell/trap proof), and if you do that then the spell protecting it from being destroyed won't save it from your attacks.

Answer 2

"Waboku" protects the monster(s) of the player and the player who activated it. It does not affect opponent's monster at all. So what would happen in this scenario is:

1. Your opponent's monster will not be destroyed by battle with your immune monster.
2. Your opponent will not receive any kind of battle damage.