Sizes, ethics and print
All sizes have a bit of a generous fit.
Most clothing is American Apparel, which was recognised by PETA as best vegan-friendly clothing company (https://www.americanapparel.net/presscenter/awards.html). All other clothing is by Gildan, an ethical company as well, hoodies and sweaters are also vegan. Their clothes are very similar in size and fitting to American Apparel products. The prints are made in Britain by a print company in London, UK. Design in London by www.ertl-design.co.uk
If you prefer a snug/slim fit I would recommend a size lower.
To give you an example, I am 6'1, 82kg and athletic and M fits me well, a S would be very slim fit for me.
For a tight fit I recommend for female t-shirts to pick a size one below your usual to ensure a tight fit.
For unisex clothing I recommend girls to choose two sizes below your usual fit and for guys your usual size or one size below for a snug/slim fit (see above male sizes).
Prints and sizes on the models depicted in the shop are for visual purposes only.