Good Ending starts out great. We have a guy (Utsumi) who's insecure about himself, and he's got a crush on this girl who plays tennis. She's really nice, which is why he likes her. Another girl, Yuki, can tell Utsumi likes the tennis girl, so she decides to help him overcome his insecurities and help them get together.
Utsumi joins the tennis club, and finally gets to talk to his crush. They talk, they have fun, they even go on a sort of date because Yuki was pushing Utsumi to do it. However, when he finally confesses, she rejects him, saying she already has someone she likes.
Utsumi then directs his affections to Yuki, the girl who helped him get together with the tennis girl. He realizes he loves Yuki, and wants to be with her, but doesn't know how to tell her.
This is where Good Ending becomes Endless Bad Ending.
Suddenly not only does Yuki secretly like Utsumi as well, but some big breasted bimbo has set her heart on concurring Utsumi by literally raping him, and the tennis girl has a change of hearts and likes Utsumi now as well. All these girls like him, and even though Utsumi said he loved Yuki, he can be so easily manipulated by the big breasted bimbo and the tennis girl. Both times he wanted to have sex with them (and would have if they weren't interrupted), even though he apparently loves Yuki.
This manga just endlessly cycles through the same damn formula again and again, and keeps adding more people that want to throw themselves at Utsumi (turned into a harem). I guess that's what you get for being a shonen romance manga. I have given up hope that it will turn out good, because this isn't worth saving anymore. It started out great, but it definitely left a bad aftertaste in my mouth.