Tales of Wedding Rings _(Kekkon Yubiwa Monogatari)_ is an animation in the Isekai category.
This is a tale with a male protagonist, Haruto Satou, that meets his childhood friend, princess Krystal Novaty “Hime” Nokanatika, who is from another world. Haruto happened to be around when Hime and her "grandfather", a high-court mage, appeared in the forest through a bright column of light. Hime ask Haruto not tell anyone of their arrival and that begins their ten-year friendship.
The adventure begins when the time arrives for Hime to return on her sixteenth(?) birthday. Conincidently, Haruto decides he is no longer satisfied with their friendship status and plans to confess to Hime (he-may). His world is shattered as Hime tells him their time together is done and she has to return home to get married. Not willing to accept letting Hime go, Haruto follows her and her grandfather into the column of light in which they arrived.
Hime gets the surprise of her life when Haruto appears in the middle of the wedding ceremony. Before anyone can do anything about it, Hime rushes to Haruto kissing him and activating the wedding rings she's always kept on her necklace. By ritual and ceremony Haruto becomes the land's hero. It is a shock to Haruto because his now someone's husband, the land's hero, and the only one who has a hope of defying the soon-to-be active Demonlord.
But Haruto's power is not at full strength and he has to collect the other four rings that will give him enough power to vanquish the Demonlord...so he must get married four more times to four different races of women. Will Haruto be able to make room in his heart when Hime already fills the space? Will Hime, having already known she was going to be part of a harem, be able to accept her place by moving aside and making room for the other girls? In order for the rings to reach their full potential can Haruto synchronize with the other girls on the intimate level needed? Can all of it be done in time to defeat the Demonlord before he takes over the world completely? These are the headscratchers that can only be answered by watching _Tales of Wedding Rings_!

It's an okay anime with both subtitles and dubbed versions. There is mild nudity and basic violence. It can definitely be rated 13+ with the amount of risque scenes, situations, and dialogue. If I had to rate it, this anime sits somewhere between _Sekirei_ and _Maken-ki_ , but with better dialogue and plot. Like I said, it didn't exactly blow me away, but _Tales of Wedding Rings_ was certainly better than meh. I don't regret watching it. Take that for what you will.

Good Luck in your viewing! -- Bob --