Little sister trying so hard to jerk off, her cock hard and leaking, her hand gripping tight and stroking hard but she just can't finish, it just won't work when she's on her own--until big brother hears her struggling and decides to check on her. She's mortified to be caught, but more than anything she's frustrated to the point of tears. But it's alright. Big brother loves her, and he knows just how to help. He lays down in her bed and spreads his legs, his cunt already wet for her. He guides her gently, lining up her hips, positioning her cock to push inside him. She presses her hips, and he accepts her fully. He strokes her hair and soothes, encouraging her to move her hips. He'll help her. He'll be here as long as she wants. There's no need for frustration and tears. And her big brother's voice, always so supportive, helps her calm down, and she starts to thrust. Immediately, it feels better than her hand. She knew her big brother could help. He's always so nice to her. She moves faster and faster, her cock getting harder. The movements get slicker. Her big brother's hot cunt feels so good around her. She thrusts deeper. Even as big brother's breath hastens, even as his own hips tremble, he reassures her. Good girl. Just like that. Do what you need. Swing your hips, nice and deep, there you go. Good girl. Your brother's here for you. And she spills inside him, finally able to cum thanks to her beloved big brother's help. She knows he's always there for her.