ムネが躍るイタズラな夏 is a Weiß Schwarz card from ブラウンダスト2 BRD/W139-022. Compare listings from Singapore Weiß Schwarz sellers on CardJio, then jio them on WhatsApp.
If you don't have a 《RPG》 character, or if you are level 3 or higher, this cannot be played from hand. Choose 1 of your opponent's characters, this turn, it gains the following ability, "【AUTO】 When this is sent from Stage to Waiting Room, deal 1 damage to yourself."
This card was printed in Japanese only; the English text above is an unofficial community translation.