@Winterfire
I read your post and find that I don't like how you are using "realism". And I can't tell if people who do this are being intentionally dense or what, but what people are asking for when they ask for realism in media isn't for things to be as mundane and boring as reality, but for the developer to take the time to establish the reality of their world. If your characters are the "Oh you have a boner, let me help you take care of that type" they have to consistently be that type. I know you didn't read the comments before posting, but both myself and another user provided Nudists and new age sex positivity as lenses through which a character could be written who might be less averse to dicks, and maybe even open enough to help. Other ideas, you could write an older sister character in the Ara Ara One-san archetype, to where she'd see helping you through this as a way to both service her desires and have a certain power over you through sex. When someone has a problem with realism they aren't saying your work isn't a perfect reflection of reality, they're saying it doesn't take the time to make us believe what is happening.
@Joshua Tree
That, exactly, is what I'm trying to say. Craft a character who we can believe would take this action, and we'll follow you down the rabbit hole.
@freedom.call
You're falling into the same trap I'm trying to talk about here too. Realism =/ create a perfect mirror of reality. It means, make me believe where I am. Waifu Academy is an over the top insane world, but, I believe it, it has realism. Meanwhile, I find myself taken out of games like Big Brother and Man of the House which have more grounded realities, and then violate the rules of their established realities.
@Obsidu
My game starts on a believable sex scene. What people want is to maintain suspension of disbelief. Make us believe that something can happen in your world and we won't be taken aback when it does. Having the prudish mother character suddenly salivate at the thought of your dick without justifying it in any way is literally making your dick into a deus ex machina.