Spell of Desire

Spell of Desire (魔女の媚薬, Majo no Biyaku) is a manga by Tomu Ohmi. It was serialized in the Petit Comic manga magazine from October 8, 2011 to October 8, 2013. It is complete in five volumes. Viz Media has licensed it for English release.

Plot
Kaoruko Mochizuki runs an herb shop in a small seaside town. One day, a mysterious man dressed in black named Kaname Hibiki enters her shop and reveals that Kaoruko is actually a witch. And what’s more, Kaoruko needs Kaname to help control her awakening power!

Official
Official English site