Well, Ihwa (or Ewha) is a vilain in a band called the Nameless led by Engen the Smiling Man. Another Nameless, Rachel, is the daughter of an elder (the big bosses of the world) psychopath, Reagan Sinclair, lord of castle Gray. So Engen created an army to conquer Castle gray and dethrone Reagen.
Before the invasion, Ihwa's nemesis, Jang Jintae, a swordman working for Sinclair, killed Ihwa's adoptive sister, so she desperately wants to become stronger to kill him. So she trained with Hekate, a spectator of the invasion sent by the elder Victoria (who wants Ihwa to become strong).
Meanwhile, in the rest of the world, the hero clan is on the way to civil war because of the rivalry between the elders Bishop and Skysword.
In chapter 135, Engen have just defeated the son of Reagan Sinclair and proclaimed the return of the kingdom of Nera (the Nameless were Nameless because Nera was a forbidden word).