The game takes place on a "steampunk" type of world.
The Dark Acolytes, a mysterious organization of cyborgs and robots, is trying to find the five legendary Sacred Flames, and bring chaos to the World in the process.
She has feelings for Meis, but finds herself often enraged by his lecherous behaviour. A 21-year-old knight and an old friend of Meis, he's brave but not too clever, and tends to freeze when in the presence of pretty girls. The 17-year-old daughter of the King of the Pirates, Wyna is a boisterous girl who loves fighting; she joins the party just to go on adventures.
She wears a bikini as well as an eyepatch, but just for effect, she's not missing any eyes.
She can be found in the huge ship called the Langoud. Metalia, the "Jewel Master", the oldest of Meis' dates, over 200 years old as said by herself, this woman was a friend of Jyabil's and helps the heroes find the flames. Combat in Thousand Arms is turn based, with up to three party members to be taken into battle at once.
Kyoka Maharoba, Soushi's sister, a shy and proper Japanese girl who detests her brother's lecherous personality (but is blind to Meis's). Mil Wind, a highly intelligent girl who stalks Meis as a way to research his womanizing personality. However, only the front character is actually able to physically attack the enemy.
The dating aspect allows the player to pick dialogue choices.
For example, one of Meis' dates asks what he thinks his best trait is during a passionate night out.
After her brother is killed by the Dark Acolytes, she decides to help Meis on his quest. His weapon of choice is a claymore, a huge sword that normal people would have a difficult time wielding.
The key feature in this game which distinguishes it from most other RPGs is its built-in mini-dating simulation.
Thousand Arms' dating sim features dating locations in many of its major cities and towns, and a cast of nine women.
Meis, a womanizing "Spirit Blacksmith" with the ability to make magical weapons, finds himself chosen to find the flames before the Dark Acolytes do.
However, to increase the power of his weapons, Meis must have the help of a woman, and must increase his 'intimacy level' with her by going out on dates.