Described as "horror behind closed doors" by the local police chief, the events took place in the village of Saint-Doulchard close to the town of Bourges in the Centre region of the country.
The woman was finally freed on August 11th after allegedly being beaten, raped and brandished with obscene tattoos and cigarette burns. It is believed that some of the woman's experiences were also filmed by her attackers.
The seven people being questioned include two men, one of whom is believed to be the woman's boyfriend, and two other women all aged from 29 to 33. The group also included three teenagers, two boys aged 14 and 16 and a 14-year-old girl.
Local newspaper Le Berry Republicain reported that the torture started after the woman was believed to have cheated on her boyfriend.
"It was horror behind closed doors," said Bruno Meunier, a police chief leading the investigation. The woman "was huddled up on a straw mattress that you wouldn't even give to an animal. Her face was all swollen up. In twenty years, I've never seen anything like it."
"I didn't think this type of place existed in Saint-Doulchard. There were six dogs, six cats, rabbits and hamsters in the house that roamed around and did their business everywhere."
The seven have admitted to what happened but deny the woman was kidnapped, prosecutors said. They are being held for further questioning. The woman herself is still in hospital recovering from her injuries.