CUTE×GUY is a manga (not yet officially translated) by Makoto Tateno.
Sumi Takaoka is a generically cute girl with a problem, she has a crush on guy — Mitsuru Sudou — who rumour says prefers buxom and mature and sexy types... everything she isn't. However, she thinks may just be in luck as her Mad Scientist father has just invented a medicine that he has promised will give her the mature and sexy attributes she desires. So, heart pounding as it it always does when she's near Misturu she downs the formula in one gulp...
...and it transforms her into a mature looking, tall, and sexy... man! And it will do so now every time her heart races as that was her condition when she drank the medicine and she'll stay male each time she does until the effects have worn off two hours later. On top of all this, her father is not only out of the country but also deeply unhelpful whenever she contacts him as he's more interested in using her as a lab rat for his new medicine (designed to replace trans masculine gender confirmation surgery) and her mother who is a stylist just wants to use her as male model. Also she finds herself aggressively lusted after by the vampish school nurse. On the plus side Misturu looks up to her male self (who seems to present a more confident front as than she does as herself) and wants to be friends, figuring she'll get to know him better this way she decides to become his mentor, acquiring the name Jun Tadano by accident.
Soon other gender benders show up, mostly male-to-female, who have either been similarly conned by her father, or in one case are related to his biggest rival — all of them with different triggers and one of whom who develops a crush on Sumi.
CUTE×GUY provides examples of of the following tropes:
- Abusive Parents: Sumi and Shizuka's fathers force gender dysphoria on their children just to use them as lab rats, and Sumi's mother is more interested in making her daughter dress up as a male model as she wanted a boy anyway.
- Attractive Bent-Gender: Sumi is your cute but averagely-so-looking shojo lead. Jun on the other hand is tall, toned, and looks older than his years in a good way. Sumi also carries herself better as Jun and seems effortless cool and charming — then you cut to a (still male) Jun freaking out and wondering why just as he's running off somewhere.
- Birds of a Feather: Sumi ends up being close friends with Hozumi due to their shared Gender Bender abilities.
- Gender-Bender Friendship: The main premise for the plot, at least until other gender benders show up.
- First Law of Gender-Bending: Despite the main lead being a rare example of a female-to-male gender-bent character who has it as a recurring problem rather than a one-off, most of the other gender-bent people she meets are male to female. The only other female-to-male she meets is cured fairly quickly and forgets it ever happened to her.
- Hospital Hottie: Kyoko-sensei, blonde, buxom, sultry and a (in this case school) nurse.
- Teacher/Student Romance: Kyoko-sensei, the school nurse, very popular amongst the male students at Sumi's school, comes on very heavily to Jun even though she initially thinks he is a (older-looking) student. She soon notices he isn't on the school register, though.
- Mistaken for Gay: Whenever Jun is out with Mitsuru giving him "manliness tips" due to the fact that they look like the archetypical Seme and Uke, they keep attracting crowds of fujoshi.
- Screw Yourself: Hozumi seems to be in love with his alternate self, and works super hard to buy lavish gifts for his female self. During Valentine's Day, Girl!Hozumi declares her intention to give chocolate to her male self.
- Sue Donym: This how Jun ends up with his surname. The name Jun is a different reading of the same Kanji as Sumi, but "Tadano" came into play when Kyoko-sensei asked for Jun's full name again and got "Ta da no Jun!" or "It's just Jun!" — and misheard it as "Tadano Jun".
- The Vamp: Kyoko-sensei the school nurse, not only is beloved by the schools male population (most of them anyway) but almost forces herself of Jun/male Sumi until she gets the brush off.
- Yaoi Fangirl: Small crowds of them flock to Jun and Mitsuru whenever they are out together as the two really look (and act) the part of a seme and uke.