Sango is pretty much a closed off character when it comes to expressing herself to someone. However, as the final days are approaching to the last battle with Naraku, Sango becomes more open about how much she loves Miroku.

During Episode 3 of the Final Act, Sango, who is depressed because of Kohaku and everything else happening around them, tells Miroku that he can leave her side and distract himself elsewhere, as long as it's not with other women. However, Miroku tells her that he can't do that because "it's times like this that I need to be by your side. I could never leave you to go fool around," Sango rubs Miroku's butt, and says she only did it because she had hoped that it wasn't Shippou disguised as Miroku. She smiles at him and tells him she is glad that he is the real one. Sango begins to let her guard down even more, letting Miroku stay by her side when she is in pain, rather than being alone. This scene makes me really happy because we see Sango touching Miroku inappropriately. I know it was just because she was suspicious of his kind words, but it's also ironic that Miroku is able to keep his hands off of her now, but she puts her hands on him.

We also see this in Episode 153, where Sango is stressing over similar things, and Miroku stays by her side because Sango ASKS him to stay with her.
Miroku: I don't want to see you suffer. Is there something I can do for you?
Sango: Can you... just stay here with me?
Miroku Sure thing. Don't worry Sango, I won't stroke your butt.
Sango: Yes, keep your hands off for now.
We find out when Sango is finally ready to be "hands-on" with Miroku during Episode 19 of the Final Act. Sango has become more handsy with Miroku know, showing that her desire for him is more physical at this point, which is implied that its more meaningful and romantic now than it was. Miroku was badly hurt by Magatsuhi when trying to absorb him in with his Wind Tunnel again. Miroku gets knocked out and brought back to the village. However, Kohaku was taken, so Sango realizes that she needs to leave Miroku for the time being. She leans down and kisses him while he's asleep, telling him that she wants him to survive for her and their future together. She wants the promise of bearing his children once the battle is over to be fulfilled badly, but she also knows she can't abandoned her brother. She also hopes that she will be safe as well, because she knows Miroku would be devastated if she wouldn't return.

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