The JLS star's bandmate Aston Merrygold praised their relationship, telling Heat that Wiseman phones him to find out what Marvin likes before buying him surprise gifts.
Humes said: "I'm very loved-up. She's an incredible girl. She's extremely thoughtful and very generous to everyone."
Merrygold quipped: "It's true love, isn't it? It's lovely, like a fairytale. It makes you a little bit sick because you haven't got it, though."
When asked if Humes put on "baby voices" for Wiseman, fellow JLS star Jonathan 'JB' Gill said: "He's always doing baby voices. He loves putting them on. He's got a little nephew, so he's always doing it. I think he's in a broody state at the moment!"
Humes replied: "These lot are always ripping it out of me for doing baby voices to the dogs."