Reaching the needed amount of goals increases the level of the adventurer. Goals don't progress if the dungeon is below a certain level however (it will show in the overview while in that dungeon). Since there are no very hard dungeons, it is impossible to get to level 4. Could you check whether the lack of progress for Tomo isn't just due to her running easy dungeons?
Viewing post in Ero Dungeons [Old Version] comments
You were right, when I finish the medium level dungeons, Tomo can fulfill her goals. However can it be, that only one goal per finished dungeon can be fulfilled? Because after finishing the dungeon Tomo had more then 60 lust, but this goal has not changed. BTW, the grey bar at the edge of the goals, looks like it should have a function (scrolling?). For me this grey bar does noting. Hope this information helps. Have ha nice day.