This can be listed like an activity which can be done in Koh Chang, and Koh Chang is the perfect place for that.
Why not to spend your Honeymoon on Koh Chang? This small paradise island is also very romantic.
There are lots of resorts which are proposing Honeymoon packages. They normally include a room decorated with lots of flowers, heart shapes on the bed and towels sculptures, a welcome bottle of wine, sometimes a romantic dinner on the beach and in some case a massage in their spa.
But even if it's not written on the resort's website, they may arrange something for you and it can be free of charge compared to the packages.
Just contact in advance the hotel or resort you are planning to book. Tell them that you are planning to spend your Honeymoon at their place and you want to know if they can org anise something. You can also look at their Facebook pages, they often post pictures of such decorations.
My favourite resort for lovers is Koh Chang Paradise Resort & Spa. They know how to make you feel like a special guest.
Even small resorts like Boonya Resort can arrange nice surprises.
And why not to take a professional photographer to immortalize this romantic time on the island?
There are lots of photographers on Koh Chang like Phusitphotography for example. He will bring you different spots. You will get a beautiful set of pictures.