Now really lovestruck Admirals have marriages recognized in the 3D world
Back on Valentine's Day, the KanColle free-to-play browser game that introduced the whole fleet girl multi-media phenomenon introduced an interesting way of monetizing the endeavour. You could marry your ship daughters when they reached level 99. Complete a quest to receive one "Papers and Ring" item for free. Additional rings for that harem will cost 700 yen each in the item shop.
Now, for really lovestruck Admirals, you can buy a real ring and marriage certificate.
There are three styles of rings to reflect the ship type of your waifu: a loading machine style "mark" for ships like the regular carriers, light carriers, and seaplane tenders - a "string" for the characters who wear traditional Japanese outfits, such as the battleships like Kongo or Yamato - a "sailor tape" for characters who wear school uniforms, like cruisers, destroyers and submarines.
The SV925 silver rings are 15,000yen or 18,000yen engraved. They come with certificate, quality guarantee, box, and a glossy "photo" of the bride.
What this sort of thing looks like in-game...