Summer Fae, also known as the Sillie, are not always nice or kind. They are however, more likely to be so than Winter Fae. As with all Faeries, one cannot use previous knowledge to assume that anything is the case, it is entirely possible that a unicorn could be the most dangerous faerie you ever run into, they could very well be evil and could very well want to kill you. Normally, however, that will be because your interests counter their own. The same goes for the rest of Summer, but do not be fooled: they will not ignore grievances just because they are summer Fae.
Some Summer Fae, though there are more that I could not think of at the time I wrote this page: