Riviere and the Land of Prayer, Vol. 3 (manga)

Another day, another dollar at Riviere Antiques. After their run-in with an underwear obsessed vandal at the archives, a stranger request would be hard to come by. Or so they thought, until the Queen of Cururunelvia walked through their door…! Now, MacMillia and Riviere are off in search of someone who holds the key to everything—the former queen Marinarise’s misbegotten heir!