A Crown of Stars: Shinji is constantly looking at Asuka (incidentally she demands that he does so).
In chapter 48, Shinji is so distracted staring at Asuka's butt that he bumps against her.
Asuka:“Ow! Watch it, Third!” Shinji:“I’m sorr-“ Asuka:“I bet I could fling you off this spot hard enough to hit the roof of that truck, Third Child. What gives?” Shinji:“Um… I wasn’t watching where I was going?” Asuka:“….you were staring at my ass again, weren’t you?” Shinji:“………yes?” Asuka(smirking wickedly):“Good.”
Advice and Trust: Shinji had a hard time NOT gawking openly at Asuka's body. After getting together it is even harder for him. He stares at her the whole time but he still tries to be discreet about it since they are trying to keep a Secret Relationship.
In chapter 3 Asuka is (pretending) lecturing him about the water being too hot, but Shinji is barely keeping track of the conversation since he is too busy staring at her bare legs.
A small part of his brain was concentrating on not dropping the hot pot on his feet, because most of it was trying not to drool helplessly over the way Asuka's long, smooth legs disappeared up under the hem of the towel, mixed in with memories of last night that said sight triggered.
Navarone regularly does this in Diaries of a Madman and openly admits it in his narration, particularly later on in the story as he becomes more depraved.
Chapter 2 gave an example that amusingly combined this with Female Gaze: the three pilots go to buy new clothes, Rei tries a new dress... and Shinji and Asuka can not take their eyes off her, noticing how the dress clung to her body and showed her curves.
Evangelion 303: This doujin's female characters provide plenty eye candy, especially Asuka.
Superwomen of Eva 2: Lone Heir of Krypton: The narration notes several times that Asuka’s costumes inevitably draw the eye to her bosom cause the “boob window” of the first outfit and the S” emblem of the second.
Her tight blue shirt made her not inconsiderable curves very apparent, and the yellow and red shield emblem with the "S" inside it on her chest only served to draw the eye to that area.
In chapter 2 of Last Child of Krypton, Kaji and Shinji walk behind Misato and Asuka. Kaji advises Shinji to let them walk in front in order to enjoy the “sight”.
Loki: Agent of Doomgard in-universe example: Mini!Thunderstrike met Story!Loki as a woman first so he planed to spend the time on the assignment with ogling her ass... who at that point decided to changed gender to male for Thunderstrike's great disappointment. Loki pointing out that he can still do the ogling "somehow" didn't make him feel any better.
In the main story, at the beginning of the Mewtwo Strikes Back arc, Ash and his female companions are enjoying a day off at the beach. At one point Misty comes out of the water after some diving, and Ash stares at her bikini-clad body, with the narration even mentioning how he follows a droplet as it rolls down her cleavage and then her stomach.