From left: Feena, Sayaka, Natsuki, Wreathlit, Mia, Mai.
At some point in the past, colonists from Earth established the Kingdom of Sphere on the Moon. Tensions between the Lunarians and the Earthlings led to the Oedipus War, a conflict that left both sides badly mauled. Since that time, the Earth (now unified under the United Nations banner) and the Kingdom of Sphere have shared an uneasy peace...Tatsuya Asagiri is enamored with the moon. Ever since he was very young and met a girl who claimed to be from the moon, he has always wanted to travel there. Fate then drops an almost literal meteor on him when it is revealed that, in an effort to further normalize relations between Earth and the Moon, the Princess of Sphere, Feena Fam Earthlight, will be staying at Tatsuya's house and attending his school as an exchange student...The fourth game of Visual Novel maker August Soft, it has several iterations, including the original X-rated PC game (simply Yoake mae Yori Ruriiro Na), a manga (same title) a PS2 adaptation (subtitled ~Brighter than Dawning Blue~), an anime adaptation (subtitled ~Cresent Love~), and an X-rated collection of side stories for the PC (subtitled ~Moonlight Cradle~). Sentai Filmworks used the title Brighter Than The Dawning Blue for their English subtitled version of the anime.
Bleached Underpants: The original game was an H-game, but the anime adaptation and PS2 port have the sex scenes removed.
Butt Monkey: Jin. In the game, he gets a pan to the face from Natsuki each time he's doing and/or saying something silly; and in the anime, him being punted through windows and having his wages garnished to pay for the repairs is a running gag.
Brother-Sister Incest: Sort of. In the game, Sayaka (actually Tatsuya's cousin) and Mai (adopted) are both available haremettes.
Double subverted in the anime, where Mai is related by blood and neither wins.
Cultural Cross Reference: In Wreathlit's route in Moonlight Cradle, there's a scene in which Stars and Stripes Forever plays in the background. Also, the references to Alien and Indiana Jones under Shout Out.
Fantastic Racism: Most of the Moon people have an hatred of Earthlings due to the bad blood between Moon and Earth. The theme is particulary explored in Feena's and Estel's Routes, with the most blatant offenders among the characters being pre-Character Development!Estel in the game, and Jurgen in the anime.
Impossible Task: Karen, who's the person the King of Sphere has entrusted with judging potential husbands for Feena, and can't approve of Feena and Tatsuya's relationship in Feena's Route (due to him being an Earthling and a commoner), sets one on them: Tatsuya has to defeat Feena in a kendo match. Problem is, Tatsuya has never practiced kendo, Feena is an expert kendoka, and he only has one week to prepare for the match... Feena defeats him, but it ultmately turns out to be a Secret Test of Character, in order to test their determination. They pass the test with flying colors, allowing Karen to fully support them.
Lethal Chef: Natsuki, called the "Carbon Master" because everything she cooks winds up looking like charcoal (even a salad in the anime).
Missing Mom: Mothers really don't fare well in this one: Tatsuya and Feena both had their mothers die (around the same time, no less), and Jin and Natsuki's mother is off training somewhere during the events of the games and anime.
Jin and Natsuki's mom does make an appearance in the last episode of the anime though, at Tatsuya and Feena's wedding.
Really 700 Years Old: Fiacca and Cynthia Marguerite, both are scientists of the war 500-700 years ago. Justified in both cases where Fiacca has many people as vessels and Wreathlit is only the current one, and Cynthia has been put in a time machine, but doesn't age since time doesn't flow inside.
Space Cold War: After the Oedipus War ended, Earth and the Moon share an uneasy peace. Feena's term as an exchange student on Earth is a move intended to further the normalization of relations.
Another Side, Another Story: At various points of the routes, the story's point of view changes from Tatsuya, to another character (often, but not limited to, the route's heroine), allowing to the player to know the feelings of those characters. Those events are called "Another View" in the game.
Ascended Extra: Midori Tohyama, Tatsuya's classmate, has been one of the possible love interests since PS2 adaption. Estel Freesia also fits, in that she appears in Feena's ending in the PS2 and MC versions, whereas she didn't appear in the PC original.
The Atoner: Priest Moritz, who, in various Another View events, mentions he's in penance for something terrible he did in the past. The nature of his sin is the final Reveal of Estel's Route: he was a noble from a cream-of-the-crop Lunarian house, who, 20 years before, was appointed as the first ambassador of the newly built Lunarian Embassy on Earth. He had a daughter he adored, named Freesia, who, before he knew it, fell in love with an Earthling. Getting wind of this, Moritz forcefully separated them, but later discovered she was pregnant with their child, and she kept it in spite of her father's opposition. The baby was born, but Moritz, not accepting the situation, abandoned it at an orphanage behind Freesia's back. Freesia died from the emotional shock, causing Moritz to deeply regret his actions, and wanting to take back the baby and raise it. The orphanage refused, so he decided to throw away his noble title, and enter the orders, so he could watch over the baby and help as many people as possible. And who was that baby? Estel.
Cannot Spit It Out: Tatsuya neatly averts it in Estel's Route. He confesses his feelings to her as soon as he realizes them, but she refuses her confession, as, by this point of the storyline, while she has begun to fall in love with him, she still hasn't fully sorted out her Fantastic Racism issues. Tatsuya, realizing this, decides not to give up, and to patiently melt her armor some more before trying again.
Cuteness Proximity: Estel, who's a covert dog lover and literally melts upon meeting one. Tatsuya accidentally discovers her secret at the beginning of her Route, much to her embarassement, and it becomes an important part in cracking her armor.
Dead Guy Junior: Estel, whose family name is, unbeknownst to her, the first name of her biological mother, Freesia.
Fan Translation: A work in progress. Erengy Projects, the same group which translated Canvas 2, is striving to translate a worksafe Windows version.
Tears of Joy: Estel sheds these upon seeing the kindness of everyone, after the conference she and Tatsuya organized together is successfully over, in the climax of her Route.
Trademark Favorite Food: Cream puffs for Feena. The scene where she eats one for the first time is even treated as if she had eaten an Impossibly Delicious Food, with her gushing about the taste (when the other characters have a normal "delicious" reaction) while Love Bubbles appear in the background.
Chekhov's Gun: In episode 4, Tatsuya and Mai jokingly mention that their dad was investigating 'alien ruins' and might have been abducted. Sayaka and the President look at pictures of a UFO in passing and suspect it is a new Lunar ship. Then when Tatasuya gets shot in the last episode, aliens save his life (partly because his father had been traveling with them).
Shout Out: In episode 4 and his appearance in the last episode, Tatsuya's dad carries a whip and wears a fedora, much like Indiana Jones. Also in the 4th episode, Feena goes Rambo on the bugs in the study using a motion detector and a BFG ala Aliens, in order to save her protegee Mia (like Ripley did for Newt); she also calls Karen for reinforcements, who comes in a AliensDrop Ship-lookalike and pulverizes the Asagiri house LV-426-style.