Irene Belserion is the secondary antagonist of Fairy Tail, she is female and currently 400+ years old. She is the 18th most popular waifu in Fairy Tail according to MyWaifuList, next to Meredy. Her daughter, Erza Scarlet, is the most popular overall.
Irene is shown to be somewhat insane, but despite that she was able to sacrifice herself for Erza to live. She is very confident of her own power, as she was able to enchant the entire Kingdom of Fiore causing it to be a fraction of its original size. She was also not afraid of confronting Agnologia, the most powerful character in the series, and making a joke about spanking in front of her master, Zeref Dragneel, one of the most powerful characters in the series.
Irene is a skilled enchanter so much so that she has the title of “High Enchanter”. She created Dragon Slayer Magic. She is extremely knowledgeable of magic due to her 400+ years of existence, and is able to enchant entire landmasses to a whim. She is even able to send a huge meteor from space to crash by simply enchanting it.
Her consciousness currently resides within the body of Wendy Marvell, where she is able to manifest at will, and assist her at battle if needed.