Usotsuki Lily

Hinata Saotome thinks her wildest dreams came true when she is asked out by the gorgeous En Shinohara. She would soon wish that it remained a dream, as she realizes that En is the cross-dressing boy at their school. He harbors a hatred for men, so much that he'd punch out his own reflection if he ever saw it, and his cross-dressing is his way of combating that. Hinata goes out with him anyway, and Hilarity Ensues as they try to make their relationship work.

Usotsuki Lily, also known as Liar Lily, is a romantic comedy manga by Ayumi Komura that debuted in 2009 and is ongoing.

Usotsuki Lily provides examples of:

 * Always Identical Twins: The Hashimoto and Sawamura twins, who are coincidentally dating.
 * Attractive Bent Gender: En makes for a good-looking girl, enough that other guys want to go out with him.
 * Hinata makes for a charming boy, which is such that girls want to go out with her. And the fact that she looks like her brother when she crossdresses is what makes him popular when he enrolls in the same school.
 * Badass: Naota's father. A Self Made Man with a Kaiser mustache who's hobby is muscle training and sets up traps in the Takanashi home.
 * Berserk Button: Just seeing his own reflection is enough for En to smash whatever caused him to see it. Toned down as the manga went on.
 * Bi the Way: The eldest Shinohara brother, An, says that he's okay with both men and women, so long as they're cute.
 * Breaking the Fourth Wall: The characters will speak like they're aware they're in a manga. Most notable is Hinata questioning her main character status when she's not the focus of a chapter.
 * The Casanova: En's father, Shinnosuke. It causes friction with his wife.
 * Cherry Blossoms: Kojiro always has cherry blossoms falling around him, but only in season. It changes to leaves in the fall.
 * Date Peepers: Hinata followed Taiyou and En's date, and jumped out and interrupted it when her brother was about to kiss her boyfriend.
 * Does Not Like Men: En is a male example of this. The only men he doesn't snap at are his family and only male friend Naota.
 * Dude Looks Like a Lady: The youngest Shinohara brother, Ten, is cute enough to pass for a girl. He probably didn't even need the wig when he crossdressed to get Taiyou's attention.
 * Even the Girls Want Her: Hinata's popular with the girls whenever she crossdresses. The fact that her brother looks like her when she does is actually what makes him so popular when he enrolls in the same school.
 * Everyone Calls Him Barkeep: The Class Rep. We only get his name in Chapter 35, and it's Souichirou Aikawa, by the way.
 * Get a Hold of Yourself Man: Delivered by Roar-kun to Reina when she was worrying and driving herself low about her feelings for Naota.
 * Head Pet: Reina-senpai's Roar-kun, although he actually spends more time on her shoulder than her head.
 * Heterosexual Life Partners: En and Naota.
 * Huge Schoolgirl: Gotou, it's what made her incredibly insecure about herself to the point of pursuing En, simply because he says he considers all girls cute. She gets helped out of this when she notices the Class Rep taking an interest in her regardless of her height.
 * Hypocritical Humor: "This guy has strange tastes, doesn't he? I can't understand it at all." Says En the crossdresser about his brother, Ten's homosexuality. Funnily enough, he becomes supportive when Ten becomes interested in Taiyou.
 * Same chapter, same family. Ken says that Hinata must be strange to fall for a perverted crossdresser like En. The guy who dotes upon said crossdresser and asserts that En is better when crossdressing (which is a sentiment others share).
 * Identity Amnesia: En gets hit on the head with a bucket of water in Chapter 15, and begins believing he is actually a girl. He gets better, thankfully.
 * It happen's again in Chapter 36, only instead of a girly-girly girl, En's personality inverts itself into a He Man Woman Hater.
 * Lethal Chef: The Hashimoto twins. Their cooking is so lethal that it can even poison cockroaches to death.
 * Nice Guy: How Taiyou is popular in his own right.
 * Nosebleed: Happens to Hinata whenever she confronts a really cute guy.
 * Samurai: Kojirou dresses like one due to his being a samurai otaku.
 * School Festival: Chapter 6 focuses on this. Hinata's and En's classes do cross-dressing cafes, girls-as-boys and boys-as-girls, respectively.
 * Senpai Kohai: Reina's a third year, and as such is referred to as 'senpai' by everyone else in the cast, even when she gets together with Naota.
 * Second Year Protagonist: Enforced. The cast didn't move up a year since the main characters became second years, which pisses Taiyou off since he wanted to pursue a relationship as a second year. It was also pointed out that Reina shouldn't graduate just as she and Naota had their Relationship Upgrade.
 * Serious Business: Cross-dressing, for En, who dislikes Shirota for putting on a dress and a wig just so Hinata would notice him.
 * Straight Gay: Ten Shinohara, who doesn't quite hit enough points to be properly defined in any other trope, but is confirmed to be gay and currently in love with Taiyou.
 * Supreme Chef: Komachi, who was noted as not being any good before, but improved greatly upon getting together with Kojirou.
 * Tsundere: The manager.
 * Also Reina, described as an archetypal tsundere.
 * Rawr seems to be one as well, being very ambivalent towards Naota. One one hand, he does like him, especially after his helping Reina out when she got a fever, but he doesn't want to be seen being nice to him.
 * Wholesome Crossdresser: En, of course. Hinata cross-dresses occasionally, usually during work, and Gotou eventually becomes one as well.
 * Yonkoma: Chapter 35 was done in this manner.
 * Younger Than They Look: Kojirou. He's the same age as Taiyou, but looks older than Komachi, his girlfriend.
 * Yuri Fan: The new character in chapter 38, Shirota, who was so enamoured of series' main couple that he harasses En a few times and tries to get him to act more feminine.