WARNING: The following contains spoilers for Boruto: Naruto Next Generations Episode 191, "Stray Dog," now streaming on Crunchyroll.
The Boruto anime has done a great job of fleshing out Sumire, truly creating an organic bond between her and Boruto after he helped her achieve redemption. Initially sent as a weapon by the Root to destroy the village, he got her to understand the concept of family and why she could fulfill her dream as a scientist in Konoha.
However, a very important arrival on the outskirts of the Hidden Leaf Village sets up an intriguing love triangle with her and the Hokage's son.
This is all due to Kawaki's presence, which seems to be unsettling Sumire as she begins to draw parallels to her own past. He duped her to escape the Ryutan lab, even getting into a bit of a fight. It didn't end well for him, though, as her pet, Nue, bit him and they've been tracking Kawaki since then.
They want to get to the teen before Ryutan's cops get too aggressive and there's collateral damage. Sumire knows his power and chakra levels are off the charts, and while it's about protecting the public, she also wants to protect him as he doesn't understand the engineering behind his body or his nature as a weapon of mass destruction. In short, she sees herself in him, and it's less pity, more compassion and more empathy. She had her agency taken away from her too, with Danzo's followers and her own dad making her into a threat with Nue, so she understands what Kara's done to Kawaki.
And make no mistake -- when she finds him, as much as Kawaki and Nue hate each other, Sumire still risks it to tend to Kawaki's wounds. She also helps him patch up a stray dog they encounter, which again is another parallel to how they were: discarded, misunderstood and with the potential to be abandoned if they couldn't serve a purpose. Interestingly, as stubborn as he is, Kawaki does realize he has an emotional connection to her, and she's found blushing as well as he lets her in.
It spices things up as the anime recently showed Sumire and Boruto in their crush phase, but she may well relate to Kawaki more. This could be an improved take on how Sakura wanted to save Sasuke years ago. The Boruto manga has also followed this angle later on, with Sumire as Kawaki's caretaker and having an affinity for his wellbeing.
And it definitely does feel more than platonic, with Kawaki even a bit jealous that she and Boruto have a connection. Only time will tell how all this plays out, but seeing Boruto get territorial when he finds them together at the end indicates it's going to be dramatic and with many more fireworks than your average soap opera.