
Derawan Island – Beautiful scenery and beaches with special reserved rare flora and fauna will welcome you in this island. There are also caves inhabited by various crabs. This Island is occupied by Bajau people, living in their traditional villages, and even in the stilt houses build in the sea. Derawan sea gardens are beautiful, the paradise white beaches and coastal forests are inhabited by sea birds, iguanas, and swallows.
Maratua Island – It's another island in Kalimantan you can visit for your Borneo honeymoon. The island is beautiful with a small lake and bay facing the Sulawesi Sea. You can do some water sports together for an exhilarating romantic honeymoon like speedboat racing, canoe races, scuba diving, and water skiing.

Kakaban Island – There is mangrove fringed lake inside the island. The lake itself is about 17 meters deep of brackish water with a green algae bottom, sea life diverse from four types of jellyfish, snakes, purple and yellow clams on the branches.
Well, those islands could be on your Borneo honeymoon place to visit list. Spending time together accompanied with the beauty of nature and sea creatures will make your honeymoon like in the mermaid land.
I suggest you check out my other guide on Unique Trips and West Papua