Thanks for playing! I'm glad you enjoyed it :')
You upgrade your buffs just by pulling on the gacha (each banner upgrades a specific buff, listed on the top left corner of the gacha screen) from the results screen, and you get currency for pulling on the gacha by sleeping past the energy cap. If I had more time, I would have improved the tutorial, among many other things ^-^"
Nonetheless, I'm really happy you liked the art!!