User blog comment:Clover G OPTC/New to game CD count/@comment-29682895-20170706104749/@comment-29682895-20170706110107

You can get Skill Books from certain Fortnights on the Extra Isle. You can see which FNs have your character's Skill Book by going to their character page (under Manual location). Note that Skill Books are NOT a guaranteed level up, but only a chance.