SaveAsPdf - Syncfusion

public async void SaveAsPdf(Stream fs, Manga manga)
        {
            var m = manga;
            var c = m.Content;

            if (fs.Length != 0) return;
            var pdf = new PdfDocument();
            var pages = await GetPages(m);
            pdf.PageSettings.SetMargins(0);


            pdf.FileStructure.IncrementalUpdate = true;
            pdf.EnableMemoryOptimization = true;
            pdf.Compression = PdfCompressionLevel.Best;


            for (var pi = 0; pi < c.ContentPages; pi++)
            {
                var section = pdf.Sections.Add();
                var mr = section.PageSettings.Margins = new PdfMargins();
                mr.All = 0;
                var page = section.Pages.Add();
                var g = page.Graphics;
                page.DefaultLayerIndex = 0;
                var pu = pages[pi];
                var client = new HttpClient();
                var im = await client.GetAsync(pu);
                var pdi = PdfImage.FromStream(im.Content.ReadAsStreamAsync().Result);

                g.DrawImage(pdi, new PointF(0, 0), g.ClientSize);
                await pdf.SaveAsync(fs);
            }
            await pdf.SaveAsync(fs);
            pdf.DocumentInformation.Title = c.ContentName;
            pdf.DocumentInformation.Author += string.Join(", ", c.ContentArtists.Select(x => x.Attribute));
            pdf.DocumentInformation.Keywords += string.Join(", ", c.ContentTags.Select(x => x.Attribute)).Replace("\"", string.Empty);
            pdf.Save(fs);
            pdf.Close(true);

            var toast = Notifications.NotifyMangaDownloaded(m);
            ToastNotificationManager.CreateToastNotifier().Show(toast);
            fs.Dispose();
        }