The following contains spoilers for Season 2, Episode 3 of Rent-a-Girlfriend, "The Return of the Girlfriend", now streaming on Crunchyroll.
In Season 2, Episode 3 of Rent-a-Girlfriend, "The Return of the Girlfriend," Kazuya Kinoshita unintentionally ramps up the intimacy with Ichinose "Mizuhara" Chizuru by grabbing the sensual body parts of her body. This is the first unpaid act of physical intimacy in their relationship that we've seen throughout the series so far.
The two also engage, face-to-face, up close, and personal. This time Mizuhara Chizuru didn't react like she usually would, pushing him away and getting angry. Mizuhara simply asks him to get off, revealing a calmer and more comfortable Mizuhara. This season, the Kazuya and Mizuhara ship sails on strong winds towards a physically romantic relationship.
After losing her key to her apartment, Mizuhara casually decides to walk in through Kazuya's apartment to check if her balcony door is locked. As Mizuhara leans over the balcony to check if hers is open, she slips and almost falls. Kazuya unintentionally whilst trying to stop her from falling grabs a hold of her butt which initiates a strong reaction from both. Surprisingly, Mizuhara doesn't shrug him off and tells Kazuya to grab her waist instead. It's clear that their relationship has taken a steep move forward. Mizuhara is comfortable with Kazuya touching her sensual spots, although embarrassed of it.
Looking at the stages of intimacy that they've gone through. They've accomplished the basics of being able to maintain strong eye contact and having deep meaningful conversations with each other. On a physical level, they've gone mouth-to-mouth with Mizuhara giving Kazuya CPR in the first season of Rent-a-Girlfriend, and they've held hands many times on their rental dates together. In this episode, they've significantly ramped up the intimacy. Kazuya's making his way up in the relationship, not only holding Mizuhara's waist but also achieving physical contact with one of the most intimately sexual parts of the human body.
Mizuhara asks Kazuya to let go of her, but not so suddenly, as she loses her balance once Kazuya lets go of her waist. The two fall and Kazuya ends up on top of Mizuhara. They share a sensual moment, with Kazuya lusting all over Mizuhara. Kazuya fears that Mizuhara is going to hit him for staring, but to Kazuya's surprise, Mizuhara gently and calmly asks him to get off. It seems as if Mizuhara is completely comfortable with Kazuya physically and emotionally, as she later shares her tragic past with him.
They've come a long way, and Mizuhara's resistant tsundereness is slowly unraveling itself. It appears that the last remaining piece to move the relationship forward is Kazuya asking Mizuhara to be his real girlfriend.