The Lights of Prague

For readers of VE Schwab and The Witcher, science and magic clash in atmospheric gaslight-era Prague.
In the quiet streets of Prague all manner of otherworldly creatures lurk in the shadows. Unbeknownst to its citizens, their only hope against the tide of predators are the dauntless lamplighters - a secret elite of monster hunters whose light staves off the darkness each night. Domek Myska leads a life teeming with fraught encounters with the worst kind of evil: pijavica, bloodthirsty and soulless vampiric creatures. Despite this, Domek find solace in his moments spent in the company of his friend, the clever and beautiful Lady Ora Fischer - a widow with secrets of her own.
When Domek finds himself stalked by the spirit of the White Lady - a ghost who haunts the baroque halls of Prague castle – he stumbles across the sentient essence of a will-o'-the-wisp captured in a mysterious container. Now, as it's bearer, Domek wields its power, but the wisp, known for leading travellers to their deaths, will not be so easily controlled.
After discovering a conspiracy amongst the pijavice that could see them unleash terror on the daylight world, Domek finds himself in a race against those who aim to twist alchemical science for their own dangerous gain.