Sending a the top card of your Deck to the Graveyard and Special Summoning "Glow-Up Bulb" from the Graveyard are treated as occurring at the same time.
The effect to Special Summon "Glow-Up Bulb" itself from the Graveyard can only be activated once per Duel. Also, even if "Glow-Up Bulb" is returned to the Graveyard after its effect is activated, its effect cannot be activated again.
Even if "Glow-Up Bulb" is no longer in the Graveyard when resolving its effect, the top card of your Deck is still sent to the Graveyard. Also, if there are no cards in your Deck when resolving the effect, "Glow-Up Bulb" cannot be Special Summoned.
↑Konami Judge Program Rulings are considered unverified, as their source(s) are not publicly viewable. They are not confirmed as applicable to the TCG until they have been officially published by Konami.