Nyotai-ka

Nyotai-ka is a comedy Ecchi manga about a guy named Makoto who decided it would be amusing to troll an online dating site as a GIRL. This winds up epically backfiring when a goddess decides to intervene and make him an actual woman.

Hilarity Ensues.

Tropes used in Nyotai-ka include:

A-Cup Angst: Iwanami doesn't exactly have small breasts, but she does show jealousy Makoto as a girl is markedly larger than herself.
Be Careful What You Wish For: Why Makoto became a girl.
Bishounen: Averted by Makoto, who looks unambiguously male. Iwanami, on the other hand, plays this straight when she turns into a guy.
Clingy Jealous Girl: Iwanami can be this to some scary extremes.
Failed a Spot Check: Due to the art, it seems Iwanami failed this soon after Makoto came to work as a girl (in a suit wearing sarashi wrappings to disguise being a girl). From the audience perspective, Makoto is clearly shorter as a woman and his face and hair have visibly altered, so her not picking up on him becoming a girl is odd.
For the Lulz: Makoto's whole role in the plot was triggered by his tendencies for this. His transformation was, in part, the result of this trope by a goddess' tendencies towards this.
Gender Bender: Of both guy turning into girl and girl turning into guy types.
- Both Makoto and later Iwanami transform during a moment of intense sexual desire, which causes some rather odd problems, much in the vein of the movie Zerophilia.
God: In this case, an Indian goddess known as Nandikesvara, goddess of wealth and prosperity, the one who grants what she interprets Makoto's wishes to be. She's not evil in her intentions but she does seem to be deriving some entertainment out of the Gender Bender antics Makoto goes through, and she has an odd way of seeing how the end result of her powers affect us humans.
If It's You It's Okay: Kojima seems to not mind being with Makoto, even as a girl. Later, Iwanami starts to feel the same way especially after she turns into a guy.
I Knew It!: Makoto accuses Iwanami using this trope by name of being a lesbian after she takes a marked (at the time platonic) interest in him as a woman. She vehemently denies it. Considering she later makes out with him and even has sex with him as a girl, this is rather ironic.
I Want My Beloved to Be Happy: Kojima eventually steps aside for Iwanami, even helping Makoto patch up his relationship with her after a Not What It Looks Like scene.
The Loins Sleep Tonight: Manaka turns back into a man while with Kojima, but suffers performance anxiety.
Moe: Makoto as a girl has a talent for evoking this, often intentionally, and this is frequently lampshaded.
Meganekko: Iwanami.
Omake: Rather goofy 4koma panels at the end of each chapter featuring Nandikesvara in some rather amusing scenarios. Also, she is shown to like playing MMORPG's.
- Also, rather oddly for omakes, they do get referenced in the main story.
Power Perversion Potential: Makoto originally decides to take his transformation in stride and enjoy it. That is, until he learned the exact reasons he acquired it and the downsides it would entail.
- Later Iwanami starts to enjoy her male transformation, especially in the bedroom, and Makoto gets made her almost literal bitch at the end of Volume 2.
Psycho Lesbian: Mild, Played for Laughs version in Yagami, a friend of Iwanami who is also a doctor. She lusted after Iwanami since their school days and was shot down, but this apparently didn't faze her too much, and she immediately gets a little Cute and Psycho regarding Makoto as a girl, which Iwanami gets rather pissed over.
The Chew Toy: At least part of what happens to Makoto makes him one of these.
Welcome to My World: Pretty much the whole point of what happens to Makoto, albeit indirectly.
When a Jerk Loves A Tsundere: Makoto and Iwanami are an outstanding example of this, but unlike most examples where the guy's faults are blown out of proportion and the girl is overly violent, Makoto really can be a total male pig at times and Iwanami is often quite justified in her levels of anger in response to his actions.
Violently Protective Girlfriend: Both Iwanami and Kojima are this for Makoto as a girl. Makoto (female) is unable to be this way because he apparently is nowhere near as strong as a girl than as a guy, though the fact he hasn't learned how to compensate most likely justifies this.
Yamato Nadeshiko: Rei Kojima has the look in comparison to Iwanami, but her demeanor is nothing close to this.
Yandere: Both Iwanami and Kojima have shades of this for Makoto.