I'm not gonna dump them, but I will summarize them here.
>39: mama wants to lose weight, the gals help her out, she throws a tantrum, she achieves her goal, and right at the end she accidentally sees the gals making out with Keita.
>40: Mama tells Lisa about it and resolves to ask Keita directly. Lisa is nervous, but Mama clearly doesn't suspect her. Mama tells Keita she won't interfere, but what are his feelings/intentions towards the gals? He can't respond, and she asks him to think about his feelings and get back to her. Keita has a little breakdown realizing that he's in love with all the gals. The gals all respond of course he is / they have a special relationship / he should hold his head high and tell Mama. He two resolves to do so.
Mama declaring directly that she won't interfere kills a lot of the tension, but his isn't a high tension series anyway. Keita not fully considering the nature of the relationship is a little surprising, but it makes sense. When we see his thoughts, he's often focused on his own circumstances and issues, and doesn't go much deeper than he simply likes being together with the gals.
So that's where we're at now.
Bonus: the big revelation chapter has Reina cleaning Keita's ears, which is a pretty strong statement on their relationship specifically. We've seen her do it before of course, but still.