[Pendulum Effect]

You cannot Pendulum Summon, except LIGHT monsters (this effect cannot be negated). If you do not control any face-up monsters, other than "Melodious" monsters: You can add 1 "Melodious" Spell/Trap from your Deck to your hand. You can only use this effect of "Couplet the Melodious Songstress" once per turn.

[Card Text]

If this card is added to your hand, except by drawing it for your normal draw: You can reveal this card; Special Summon 1 Level 4 or lower "Melodious" monster from your hand or GY. If a "Melodious" Fusion Monster(s) is Special Summoned to your field, while this card is face-up in your Extra Deck (except during the Damage Step): You can place this card in your Pendulum Zone. You can only use each effect of "Couplet the Melodious Songstress" once per turn.