>put some girls with huge boobs wearing school uniform
>make story about stargazing
>put there a tsundere (as one of the heroines), shy girl getting angry if it comes to love-related topics
>all the story has to be about time travelling
>put in it otaku obsessed with manga and anime
>the whole story has be located in japan
>in one of the scenes protagonist has to fall on big boobs heroine's tits
>there has to be younger sister 'route'
>main place of the action has to be school
>?????????????????
>profit
>make story about stargazing
>put there a tsundere (as one of the heroines), shy girl getting angry if it comes to love-related topics
>all the story has to be about time travelling
>put in it otaku obsessed with manga and anime
>the whole story has be located in japan
>in one of the scenes protagonist has to fall on big boobs heroine's tits
>there has to be younger sister 'route'
>main place of the action has to be school
>?????????????????
>profit