In chambers dark where secrets lie, dost beat the drum of mortal sigh. 'Tis passion's source, of fire and woe, the silent bard of Cupid's bow.

Some people use money or a credit card for me, yet others use windows. The latter is by far the cheapest. What am I?

I might lead to art, I could be a result from a game or the act of choosing a card.

Quietly appears with a slash. Then gone in a smoky flash. Cloaked in shadow, eyes peek past. Sensei taught, a hidden class.

You might call one of these by name AGAIN, and again, and again. One of the big digital assistants is also known by this name.