Looking for a chilled space from September

I'm moving to London from Cape Town in September (I arrive on the 8th) to do a year-long master's in science communication at UCL, so I'm looking for a place that is reasonably easy to commute from into central London.

I'm pretty sociable, and am looking forward to making new friends and doing new things, but I work (I'm an illustrator and designer in conservation & development space) and will be studying, so am looking for a pretty chilled atmosphere with a desk to work from etc.

I've lived on my own for the last 17 years, so am pretty self-contained, but would enjoy cooking together, having a good chat etc.

Importantly, it's just me, but my partner will visit during the varsity breaks (we are planning to go away for most of this time though), so you'd need to be comfortable with me having a partner around for the odd week (he's very unobtrusive, I promise!). For the time he is here, I am very happy to pay extra to accommodate him.