My take on the whole story is the tragic love between the two that ultimately leads to Kana dying:
Mihoko doesn't want to see Kana suffer from the bad memories and the coach yelling at her anymore so she tries to end it all with poisoned food (without Kana knowing).
Kana finds out, but her love towards Mihoko and not wanting to make her cry makes her eat the food anyway.
Mihoko, unaware that Kana is knowingly eating the poisoned food, thinks that Kana will finally be able to have some peace (through death).
Delicious!Kana. It's all right now, Kana.Captain, you make the best cat food*!
*: the term used here also refers to serving food in a particular way.Poor Ikeda
This manga is a parody of "Kawaisou na Zou"(Poor Elephant)Here, Kana. It's food!Look, there are lots of sardines!Ikeda – who's second in the school ranking – is a clever girl.She knows that the food is poisoned.Now you don't have to fight anymore...