so the harem will contain:
1.Luna
2.Wiz
3.Eris(chris)
Now,i read some fanfics where the girls in the harem fall in love with eachother and then leave the MC.Be assured this won't happen!The girls will respect eachother and they will kiss and cuddle,but it won't be to such a point that it won't be a harem anymore.And any funny business between the girls will only happen when the MC is also present,for example,wiz and chris kiss while the MC has fun with luna.Thats it.
On the other hand,i will give Kazuma a lover,and its not megumin,its YunYun.im doing this because YunYun is with her head on her shoulders and will be able to reign in kazuma a bit.