Aelhelice

The corporate drone dies and is reborn as a witch, only to be immediately ensnared by the white-haired vampire Alice, who binds her in a blood pact! In her loli form, she's clingy and adorable, the only one you can rely on. In her mature form, she's fierce and protective, her combat prowess maxed out. The bond forged through shared blood is sweet enough to make you dizzy. Yet dark currents already churn beneath the city's surface. Beneath the blood pact lies an unsolvable mystery—their meeting was never mere coincidence...

(Source: Bilibili, translated)