Akaneiro ni Somaru Saka, Mashiro-iro Symphony: The Color of Lovers Recommendations
These series have quite a few simularities. First of, there is the young male who lives with his younger sister. He ends up helping out a female and the next day meets her at school, only to find out that she has another side to her personality. There is also a color theme.
Multiple girls like the main character. Similar art.
Graphics , story , the feeling. And both of them look like a harem game , where main character choses a path ( a girl ) and try to finish the game with that girl's ending . But of course in anime , main character doesn't understand the others feelings and ends up with not choosing any of them . Makes you mad .