This is the Sheffield constituency: The City of Sheffield wards of Broomhill & Sharrow Vale, City, Manor Castle, Nether Edge & Sharrow, and Walkley; and parts of the wards of Crookes & Crosspool, Ecclesall, Fulwood and Hillsborough.
So, who are the voters? It apparently has the youngest median age of voters in the UK, thanks to it covering large swathes of Studentland (Sheffield University, which has around 70000 students, is based in this constituency).
City, Manor, Castle, are relatively poorer areas - largely white working class, manual workers, unemployed etc, with a couple of big council and social housing estates. Hillsborough used to have a similar population but I think is trending more towards families these days, and more private housing stock.
Nether Edge and Sharrow have a quite a lot of students but also quite a high proportion of residents who have either immigrated to the uk themselves, or are the families of more established groups - quite a few from Pakistan and Bangladesh, most of Sheffield's older Chinese community, and increasing numbers of Somalis, Kurds etc.
Ecclesall, Fulwood are some of the wealthiest areas of town.
So it's a mixed constituency but heavy on the students. Sheffield is not well known for a gay/LGBTQ+ scene (you go to Manchester for that!) so it's not full of TRAs (as far as I know!) but nonetheless, the student population are probably who he's going to pitch to.
(Apologies to anyone who thinks I've painted their home turf inaccurately in the above generalisations!)